Every US Quantum Computer Runs on Foreign Parts and Foreign Inventions

Introduction

Spend enough time at quantum conferences, in board advisory sessions, or reading popular science coverage of quantum computing, and you will hear some version of the same story: quantum computing is an American invention, built on American physics, scaled by American companies, and now defended by American policy. The narrative shows up in conference keynotes (usually during the slide about Feynman), in investor pitches (“the U.S. leads in quantum”), in policy documents, and in casual conversation at every quantum industry event I have attended in the past five years. It is the water the U.S. quantum community swims in. Most of the people repeating it have never stopped to check it.

The most recent and most specific version came from Paul Dabbar. After the White House Summit on American Quantum Innovation on July 7, Dabbar wrote on LinkedIn: “The arc of the last decade, and the shape of the decade ahead, is this: America built every layer of the quantum stack one at a time, across a century, largely without knowing it was building a stack.” He described a “discovery layer” that was “built by physicists who were asking questions that had no commercial application.”

I single out Dabbar’s version because it is testable. He makes a specific, attributable claim about a specific thing (the quantum stack), with a specific scope (every layer), over a specific period (a century). That is a claim I can check.

Dabbar’s own list of layers includes discovery, culture, talent, capital, standards, industrial capacity, and markets. What follows does not pretend that those categories are identical to a technical stack. It tests the technological implication of his broader claim: whether the foundational ideas, hardware architectures, error correction methods, and enabling supply chains of modern quantum technology were substantially built in the United States. On that narrower and testable question, the record is unmistakably international. That mapping is a central project of my book Quantum Sovereignty, and this article applies the same lens to the origin question.

This matters for policy because the “we built this” rhetoric can obscure the very dependencies the administration’s formal policy documents acknowledge and are attempting to reduce. The quantum innovation executive order itself calls for supply chain analysis, development of domestic enabling technologies, and coordination with trusted allied suppliers. Those provisions clearly recognize interdependence. The rhetoric should too.

I should be clear about what I am not arguing. The United States has contributed enormously to quantum science and technology. It has one of the strongest commercial quantum computing industries in the world. IBM, Google, Microsoft, IonQ, Rigetti, Atom Computing, and PsiQuantum are all American companies (or American-headquartered, a distinction I will return to). American universities, from MIT and Harvard to Yale, Caltech, and UC Santa Barbara, have produced foundational research across every quantum modality. American federal investment, from the National Quantum Initiative Act of 2018 through the current CHIPS Act quantum allocations, has been substantial and sustained. None of that is in dispute.

What I am testing is the claim that America “built every layer.” Layer by layer, against the evidence.

A Note on Attribution

Assigning national credit for scientific work is inherently messy. Researchers move between countries. A French-born physicist working at Yale for two decades produces Yale results. A Russian-trained mathematician who moves to Caltech produces Caltech results from that point forward. Throughout this article, I credit work to the institution and country where it was performed and published. I use birthplace and training to discuss talent flows and intellectual lineage rather than to reassign institutional credit. Where the distinction matters, I say so explicitly.

The Discovery Layer: Theory and Algorithms

Dabbar’s “discovery layer” is where the claim is easiest to check and hardest to sustain. The conventional chronology, including the one I published in my own Early History of Quantum Computing article (which I will be updating after this exercise), starts with Feynman. That framing, almost universal in American accounts, is itself part of the problem.

The standard history opens with Richard Feynman’s 1981 lecture at MIT, “Simulating Physics with Computers” (published in 1982), where he argued that faithful simulation of quantum physics called for computers governed by quantum mechanics. This is the founding moment in most American accounts of quantum computing. Feynman was at Caltech. He was American. The lecture is rightly famous.

But a year earlier, in 1980, the Soviet mathematician Yuri Manin published Computable and Uncomputable in Moscow, in Russian. In the introduction, Manin anticipated the quantum computing concept: the quantum phase space scales exponentially compared to its classical counterpart, and quantum automata could therefore simulate processes that classical machines could not efficiently handle. John Preskill’s retrospective “Quantum Computing 40 Years Later” and Nature Reviews Physics’s 2022 anniversary assessment both credit Manin alongside Feynman and Paul Benioff (who, also in 1980, described a quantum mechanical Hamiltonian model of a Turing machine). Manin, Benioff, and Feynman made related but distinguishable contributions. Manin’s Russian-language publication initially received less attention in English-language histories, but priority is a matter of record.

The next foundational step was not American at all. In 1985, David Deutsch at the University of Oxford described the first universal quantum computer: a quantum system capable of efficiently simulating any other quantum system, the quantum analog of a universal Turing machine. Deutsch’s contribution is not a footnote. It is the theoretical architecture that the entire field builds on. He is British. He did the work at Oxford. He remains there.

The two algorithms that turned quantum computing from a theoretical curiosity into a national security concern were both American. Peter Shor, at AT&T Bell Labs, published his factoring algorithm in 1994. Lov Grover, also at Bell Labs, published his search algorithm in 1996. Shor’s algorithm is the single contribution most directly responsible for PQC urgency and defense spending. These are American achievements, and I give them full weight.

But the theoretical framework that determines how any of these algorithms will actually run on hardware came from Alexei Kitaev, born in Moscow, trained at the Landau Institute for Theoretical Physics. Kitaev’s 1997 toric code paper (published in Annals of Physics in 2003) created the foundation for topological quantum error correction. The surface code, which descends directly from Kitaev’s toric code and which IBM, Google, and most superconducting quantum computing roadmaps depend on, was developed further at both Russian and American institutions. He later moved to Caltech, where he has been since 2001, but the foundational toric code ideas were developed in Russia.

Then there is quantum cryptography. The BB84 protocol, the first practical quantum key distribution scheme, was published in 1984 by Charles Bennett at IBM (American) and Gilles Brassard at the Universite de Montreal (Canadian). Half-American, half-Canadian. Artur Ekert, working at Oxford (Polish-born, based in the UK and later Singapore), independently proposed entanglement-based QKD in 1991. Daniel Gottesman, who developed the stabilizer formalism that became the mathematical language of quantum error correction, is Canadian; his foundational work was done as a PhD thesis at Caltech (an American institutional contribution, by a Canadian researcher who later returned to Canada’s Perimeter Institute).

The bottom line on the theory layer: the U.S. has strong claims on Shor, Grover, Feynman, Bennett, and Benioff. But the theoretical architecture of quantum computation (Deutsch, Oxford), the error correction framework the field actually deploys (Kitaev, originating in Russia), and the quantum information theory underlying QKD (half-Canadian, with a major independent branch from Oxford) are not exclusively American achievements. Calling this layer “built by America” requires ignoring Oxford, Moscow, and Montreal.

Superconducting Qubits

Superconducting qubits power the quantum computers built by IBM, Google, Rigetti, and IQM. This is the modality with the most commercial investment and the most deployed systems. If any layer of the stack belongs to America, it should be this one.

Start at the device level. Every superconducting quantum computer runs on Josephson junctions, the quantum tunneling effect between two superconductors separated by a thin barrier. Brian Josephson predicted this effect in 1962 as a 22-year-old PhD student at the University of Cambridge. He won the Nobel Prize for it in 1973. Anderson and Rowell at Bell Labs experimentally confirmed the effect in 1963, making the intellectual lineage transatlantic from the start. But the prediction was British, from Cambridge.

The first demonstration that a superconducting qubit could actually work happened in Japan. In April 1999, Yasunobu Nakamura, Yuri Pashkin, and Jaw-Shen Tsai at NEC’s Basic Research Laboratory in Tsukuba published a Nature article demonstrating coherent control of a macroscopic quantum state in a superconducting circuit. The Japanese government itself credits this as the experimental foundation on which later American achievements, including Google’s 2019 quantum supremacy demonstration, were built.

Also in 1999, J.E. Mooij and colleagues at TU Delft in the Netherlands proposed the persistent-current flux qubit, a different superconducting qubit design. Coherent quantum dynamics in a flux qubit were experimentally demonstrated in 2003 by Chiorescu, Nakamura, Harmans, and Mooij, also at TU Delft. The flux qubit is a Dutch contribution.

The qubit design that dominates commercial systems today is the transmon, developed at Yale in 2007 by Jens Koch, Terri Yu, Jay Gambetta, Andrew Houck, David Schuster, and others, working with Robert Schoelkopf and Michel Devoret. The transmon is rightly credited to Yale. But Devoret, one of the most influential figures in the field of superconducting quantum circuits, is French-born, trained at CEA-Saclay near Paris. He spent decades at Yale, where he did much of his most important work. The transmon is a Yale result with international talent on the team, which is itself a demonstration of the U.S. system’s strength in attracting researchers from around the world.

Where the U.S. has an unambiguous lead is in scaling. IBM says it has deployed more than 90 quantum systems globally and is building the Anderon quantum foundry in Albany, New York, under a proposed USD 1 billion CHIPS Act award (currently a signed letter of intent, subject to definitive agreements). Google’s Sycamore and Willow processors have set benchmarks in computational demonstrations and error correction. Rigetti has pioneered modular multi-chip architectures. These are real engineering achievements, and they are American.

But IQM Quantum Computers, based in Espoo, Finland, is among the world leaders in on-premises system sales with 23 gate-based systems shipped. The European superconducting sector (IQM in Finland, Alice & Bob in France, QuantWare in the Netherlands) is growing. And every one of these systems, American and European alike, runs on a Josephson junction predicted in Cambridge and a qubit concept first demonstrated in Tsukuba.

The U.S. built the best factory for superconducting quantum computing. It did not invent all the parts.

Trapped Ions

The ion trap, the device that confines individual atomic ions for quantum computation, has German and American institutional foundations. Wolfgang Paul invented the radio-frequency ion trap at the University of Bonn and shared the 1989 Nobel Prize in Physics for it. Hans Dehmelt, who shared the same Nobel, was born and educated in Germany but did his Nobel-recognized ion-trap work at the University of Washington in Seattle. The 1989 Nobel cited both Paul’s work in Bonn and Dehmelt’s work in Seattle.

Trapped-ion quantum computing as a research program has been jointly led by the United States and Austria from the start. The theoretical proposal came from Ignacio Cirac and Peter Zoller at the University of Innsbruck in 1995, and the first quantum logic gate was demonstrated by Chris Monroe and Dave Wineland at NIST Boulder that same year. Wineland’s group at NIST (American) and Rainer Blatt’s group at the University of Innsbruck (Austrian) have traded landmark demonstrations for over two decades. Wineland won the Nobel Prize in 2012 for his NIST work; Blatt’s group has produced results of comparable scientific importance.

The commercial picture reflects this split. IonQ (American, founded by Chris Monroe and Jungsang Kim from the University of Maryland and Duke University) is the most prominent publicly traded trapped-ion company. But Quantinuum, which characterizes its Helios system as the most accurate commercial quantum computer based on average two-qubit gate fidelity, was formed in 2021 from the merger of Honeywell Quantum Solutions (American) and Cambridge Quantum Computing (British). Quantinuum is headquartered in the U.S., but its quantum software origins are British, and its scientific leadership spans both countries. Alpine Quantum Technologies, spun out directly from Blatt’s Innsbruck group, is Austrian.

The trapped-ion modality is a transatlantic achievement. The U.S. has strong commercial leadership, but the physics is German-American, the theoretical proposal was Austrian, and the most accurate commercial trapped-ion system has British DNA in its software stack.

Other Modalities

Beyond superconducting and trapped-ion systems, several alternative qubit technologies are competing for long-term viability. In each case, the contributions are more internationally distributed than a U.S.-centric narrative suggests.

Photonic quantum computing has three major players. PsiQuantum is headquartered in Palo Alto and recently received a proposed CHIPS Act award, but it was co-founded by Jeremy O’Brien, who built the photonic quantum computing program at the University of Bristol in the UK before moving to Silicon Valley. Xanadu is Canadian, based in Toronto. And China’s University of Science and Technology (USTC) group, led by Jian-Wei Pan, demonstrated photonic quantum advantage with their Jiuzhang processor in 2020 and again with Jiuzhang 2.0 in 2021. While Chinese photonics research operates within the broader international scientific literature on Gaussian boson sampling, the experimental capability was Chinese-led and developed domestically. The KLM protocol (Knill, Laflamme, Milburn), which established the theoretical basis for linear-optical quantum computing, was a Los Alamos and University of Queensland collaboration. The photonic modality has no single national home.

Neutral atom quantum computing is split between France and the United States. Pasqal was founded by researchers from the Institut d’Optique Graduate School and the CNRS in France, building on the group of Alain Aspect and Antoine Browaeys. QuEra Computing emerged from the Harvard-MIT Center for Ultracold Atoms. Atom Computing (American) is backed by significant venture funding. Germany also has a growing neutral-atom presence. The field is shared, with the Franco-American split the most prominent division.

Silicon spin qubits present perhaps the starkest counterexample to the “America built it” narrative. The experimental foundations of this modality are overwhelmingly Australian and Dutch. At UNSW Sydney, groups led by Michelle Simmons, Andrew Dzurak, and Andrea Morello produced major advances in atomic fabrication, CMOS-compatible architectures, and single-donor qubit control. Simmons (born in the UK, career built in Australia) was named Australian of the Year in 2018 and founded Silicon Quantum Computing (SQC); Dzurak founded Diraq. In the Netherlands, QuTech (a collaboration between TU Delft and TNO) has been a peer of the Australian groups throughout, and Intel’s silicon spin qubit program runs in partnership with QuTech. The U.S. thread in this modality is Intel’s involvement, but the science is Australian and Dutch.

Topological quantum computing rests on Kitaev’s Russian-origin theoretical framework, discussed above, with major theoretical contributions also from US-based researchers including Michael Freedman, Chetan Nayak, and Sankar Das Sarma. Microsoft (American) has pursued the experimental program for over two decades. But the experimental work on Majorana zero modes that Microsoft’s program depends on has been centered at TU Delft in the Netherlands (Leo Kouwenhoven’s group, later absorbed into Microsoft’s Dutch quantum lab) and at the University of Copenhagen in Denmark. Microsoft’s topological program is transatlantic: American in funding, corporate identity, and some of the theory, but European in its experimental base. Experimental evidence and claims of topological protection in these systems remain actively contested.

No major quantum computing modality has an exclusively American lineage. The U.S. has major players in each, often the largest commercial entities. But its strength is commercial integration of internationally originated science.

Quantum Error Correction

If there is one layer of the quantum stack where getting the attribution right matters most for CRQC timeline estimation, it is error correction. The path to a cryptographically relevant quantum computer runs through quantum error correction, and the framework the field uses was not built by one country.

The first quantum error correction code was American. Peter Shor’s 1995 nine-qubit code demonstrated that quantum errors could be corrected at all, a result that was far from obvious given the fragility of quantum states. The Knill-Laflamme conditions (American-Canadian) established the theoretical criteria for when quantum error correction is possible. Independent threshold results by Knill, Laflamme, and Zurek; Aharonov and Ben-Or; and Kitaev established that arbitrarily long computation is possible below an accuracy threshold. Preskill’s 1997 analysis (Caltech, American) helped synthesize and explain the emerging framework. These are American and American-Canadian-Israeli-Russian contributions.

But the seven-qubit code that bears Andrew Steane’s name was published in 1996 from the University of Oxford. British.

The error correction strategy at the center of the field’s roadmap to fault tolerance (the surface code and its descendants) traces back to Kitaev’s toric code, originating in Russia. The practical surface code lineage includes the influential Topological Quantum Memory paper by Dennis, Kitaev, Landahl, and Preskill (largely associated with Caltech), and later work by Fowler, Mariantoni, Martinis, and Cleland associated with UC Santa Barbara. The surface code’s development was multinational: Russian-origin theory, American institutional development at Caltech and UCSB, with Fowler (who conducted significant earlier work at the University of Melbourne in Australia) contributing to its practical engineering. When Google ran its 2024 below-threshold error correction experiment, it was running a surface code architecture with Russian, American, and Australian contributions in its lineage.

One major lower-overhead research direction is quantum low-density parity-check (qLDPC) codes. The foundational constructions in this area, the hypergraph product codes, came from Jean-Pierre Tillich and Gilles Zemor at INRIA and the Universite de Bordeaux in France. More recent breakthroughs by Anthony Leverrier and Gilles Zemor (both French) and Pavel Panteleev and Gleb Kalachev (Russian) have generated qLDPC codes with asymptotically good parameters. IBM’s bivariate-bicycle codes build on this broader qLDPC lineage.

Real-time decoding, the computational process of interpreting error syndromes fast enough to keep up with a running quantum computer, has important contributions from groups at UCL (UK), ETH Zurich (Switzerland), the University of Sydney (Australia), and several U.S. groups including MIT and IBM.

Quantum error correction has multinational foundations: early codes and threshold theory came from US, UK, Israeli, Russian, and multinational teams; surface code theory and engineering developed across Russian, American, Australian, and Canadian institutions; and modern qLDPC research has especially strong French, Russian, and US contributions.

The Enabling Stack

This is the layer where the “America built everything” claim is most clearly wrong, and where getting it wrong has the most direct policy consequences.

Every superconducting quantum computer operates at temperatures colder than outer space, typically 10-20 millikelvin. The machines that create and maintain these temperatures are dilution refrigerators, which circulate a closed-loop helium-3/helium-4 mixture. The market for dilution refrigerators is dominated by European companies.

Bluefors, based in Helsinki, Finland, is one of the dominant suppliers and reports more than 1,800 installations worldwide. Oxford Instruments NanoScience (UK) is another major player. Together with Leiden Cryogenics (Netherlands) and CryoConcept (France, owned by Air Liquide), European companies command the large majority of the dilution refrigerator market. As I have written in my cryogenic infrastructure analysis, Bluefors and Oxford Instruments together hold over 70% of the market, though precise shares vary by source and segment.

The U.S. market remains substantially dependent on foreign-headquartered cryogenic suppliers, although domestic production now exists and is expanding through Maybell Quantum in Denver and Bluefors’s Syracuse manufacturing operation (the latter through the Finnish company’s 2023 acquisition of Cryomech, a New York-based cryocooler firm). When IBM, Google, or Rigetti cool their quantum processors, most are using European-origin cooling systems.

Quantum control electronics, the instrumentation that generates and measures the precise microwave signals needed to manipulate superconducting qubits, tell a similar story. Zurich Instruments (Switzerland) has been a leading supplier of quantum control hardware. Quantum Machines (Israel) competes with its OPX+ platform. Rohde & Schwarz (Germany) provides critical microwave signal generation and analysis equipment. Keysight Technologies (American) is a significant player, but it shares the market with European and Israeli competitors.

Dilution refrigerators run on helium-3, a rare isotope. The U.S. Department of Energy stockpile (from tritium decay in nuclear weapons) is the largest single source for the global scientific market, though Russia also has tritium stockpiles. Global supply is structurally tight and demand is growing as quantum computing scales. This is a supply chain vulnerability that no single country fully controls.

On fabrication, the U.S. has stronger ground. IBM’s Albany NanoTech Complex is a world-class semiconductor R&D facility, and the planned Anderon quantum foundry, supported by a proposed USD 1 billion CHIPS Act award and USD 1 billion from IBM, would be the first purpose-built quantum chip fabrication facility. GlobalFoundries, which received a proposed USD 375 million CHIPS Act award for a multi-modality quantum foundry, is headquartered in the U.S. but remains majority-owned by the Emirati sovereign wealth fund Mubadala Investment Company. In Europe, imec (Belgium) and CEA-Leti (France) are important quantum fabrication R&D centers.

The enabling stack is where the gap between narrative and reality is widest. The CHIPS Act quantum investments signal that Commerce sees significant domestic capacity, integration, and scaling gaps across fabrication, cryogenics, control, and systems engineering. The investment portfolio is the right response to real dependencies. But the narrative framing (“we built this”) sits uneasily beside the reason for the investment. The gap is real.

Quantum Networking and Communications

BB84, the foundational quantum key distribution protocol, was half-American and half-Canadian (Bennett at IBM, Brassard at Montreal), as discussed above. The first experimental demonstration of quantum teleportation, the transfer of a quantum state from one particle to another, was performed in 1997 by Anton Zeilinger’s group at the University of Innsbruck, Austria. Zeilinger won the Nobel Prize in 2022 (shared with Alain Aspect of France and John Clauser of the United States) for experiments with entangled photons and the violation of Bell inequalities. The teleportation experiment was done in Austria.

The largest publicly documented national-scale QKD infrastructure in the world is Chinese. The Beijing-Shanghai quantum backbone, a 2,000-kilometer fiber-optic quantum key distribution network, and the Micius satellite, which demonstrated intercontinental quantum key distribution from orbit, were both developed by Jian-Wei Pan’s group at USTC. China’s quantum networking implementation capability was developed domestically, though its underlying scientific lineage, like every country’s, is international. The U.S. has quantum networking research programs (Brookhaven, Argonne, and Fermilab), but nothing approaching China’s scale of deployment.

Early QKD commercialization occurred on both sides of the Atlantic. ID Quantique was founded in Geneva, Switzerland in 2001. MagiQ Technologies was founded in New York in 1999 and claims some of the earliest commercial QKD products. Toshiba operates a leading QKD research program from its Cambridge Research Laboratory in the UK.

China leads in the scale of publicly documented QKD deployment. Early commercialization was transatlantic, and major research and deployment programs have emerged in Japan, the UK, Austria, and elsewhere. The U.S. contributed to the theory, but the networking layer is another case where the “we built this” narrative does not match the record.

Post-Quantum Cryptography

The PQC layer is worth examining because the algorithms the U.S. government is now mandating for federal systems were designed by international teams.

NIST ran the PQC standardization competition, and that organizational leadership is a real American achievement. The process that produced FIPS 203, 204, and 205 was rigorous, transparent, and effective. It is one of the best examples of American institutional capacity shaping a global technology transition. I give NIST full credit for the process.

But the algorithms themselves tell a different story.

ML-KEM (CRYSTALS-Kyber), the standard for post-quantum key encapsulation, was designed by a team of ten cryptographers. Their institutional affiliations at the time of submission: NXP Semiconductors (Netherlands), CWI (Netherlands), Ruhr-Universitat Bochum (Germany), IBM Research Zurich (Switzerland), Radboud University/Max Planck Institute (Netherlands/Germany), ENS Lyon (France), and the University of Waterloo (Canada). One team member, Tancrede Lepoint, had a U.S. affiliation (SRI International) during part of the competition. The rest were at European and Canadian institutions. The key encapsulation mechanism that EO 14412 requires for high-value assets and high-impact federal systems by the end of 2030 was designed almost entirely by Europeans and Canadians.

ML-DSA (CRYSTALS-Dilithium), the primary digital signature standard, was designed by a significantly overlapping team with similarly strong European representation. SLH-DSA (SPHINCS+), the hash-based signature standard, was designed by a team spanning TU Eindhoven (Netherlands), Ruhr-Universitat Bochum (Germany), and other European institutions. FN-DSA (FALCON), the lattice-based signature algorithm, has been selected by NIST and is undergoing standardization, with an initial draft published in late 2025. Its design was led by researchers from ENS Paris and other French institutions.

NIST designed the competition. The world designed the algorithms. That does not negate American leadership of the standards layer. It defines that leadership more accurately: the United States built a trusted global process capable of evaluating, selecting, and institutionalizing multinational cryptographic research. It also directly and specifically refutes the claim that the United States “built every layer of the quantum stack.”

The Scorecard

An honest assessment, layer by layer:

Theory and algorithms: The U.S. contributed Feynman (with Manin’s prior Soviet contribution), Shor, Grover, Bennett (with Canadian Brassard), Benioff. The UK contributed Deutsch (universal quantum computer), Ekert (E91 QKD). Russia contributed Manin (quantum computing concept), Kitaev (toric code/topological framework). Canada contributed Brassard (BB84). No single country built this layer.

Superconducting qubits: Josephson effect predicted in the UK, confirmed at Bell Labs (US). First qubit demonstrated in Japan (Nakamura, Pashkin, Tsai). Flux qubit from the Netherlands (Mooij group, TU Delft). Transmon developed at Yale with international talent. Commercial scaling led by the U.S. (IBM, Google, Rigetti) with IQM (Finland) a major competitor. U.S. leads commercial scaling but did not originate the device physics or demonstrate the first qubit.

Trapped ions: Trap physics from Germany and the US (Paul at Bonn, Dehmelt at UW). Theoretical proposal from Austria (Cirac-Zoller, Innsbruck). Experimental program co-led by U.S. (NIST/Wineland) and Austria (Innsbruck/Blatt). Commercial leadership split between U.S. (IonQ) and U.S.-UK (Quantinuum). Transatlantic.

Other modalities: Photonics split among US-UK (PsiQuantum, Bristol origins), Canada (Xanadu), and China (Jiuzhang). Neutral atoms shared between France (Pasqal) and U.S. (QuEra, Atom Computing). Silicon spin qubits led by Australia (Simmons/SQC, Dzurak/Diraq, Morello) and Netherlands (QuTech), with Intel as the U.S. participant. Topological QC theorized in Russia and the US (Kitaev, Freedman), experimentally pursued by Microsoft with Dutch and Danish experimental roots. No modality is exclusively American.

Error correction: Foundational codes from the U.S. (Shor) and UK (Steane). Threshold theorem developed independently across US, Israeli, and Russian groups. Surface code theory from Russia (Kitaev, Bravyi), developed further at Caltech, UCSB, and Melbourne. qLDPC codes from France and Russia. Multinational.

Enabling stack: Dilution refrigerators dominated by Finland (Bluefors), UK (Oxford Instruments), and Netherlands (Leiden Cryogenics). US domestic production growing (Maybell, Bluefors Syracuse) but still largely dependent on European-headquartered suppliers. Control electronics shared among Switzerland, Israel, Germany, and U.S. Fabrication stronger in the U.S. (IBM/Anderon) but with European R&D (imec, CEA-Leti). The U.S. is actively investing to reduce dependencies it did not build.

Quantum networking: Theory partially American (Bennett), partially Canadian (Brassard), with key experimental firsts from Austria (Zeilinger). Largest deployed QKD infrastructure from China. Early commercial QKD from both sides of the Atlantic. U.S. trails China in deployment.

PQC: NIST process is a U.S. organizational achievement. The algorithms were produced by multinational teams with particularly strong European representation. American institutional leadership with international algorithmic content.

Why This Matters for Policy

The point of this exercise is not to diminish American contributions. It is to test a specific claim against the evidence, because the claim has policy consequences.

Supply chain visibility. A government that believes it built the whole quantum stack risks underestimating its dependencies. The CHIPS Act investments address quantum chip fabrication, and they are the right investments. But fabrication is one layer. Who builds the dilution refrigerators that cool most superconducting quantum computers? Primarily Finnish, British, and Dutch companies. Who manufactures critical control electronics? Swiss, Israeli, and German companies alongside American ones. These dependencies do not disappear because a politician writes that America built the whole stack. They get worse if policymakers believe the narrative and fail to map the real supply chain.

And this is not a hypothetical concern. The summit itself identified supply chain vulnerability as one of three unresolved gaps. Attendees mapped roughly 160 quantum companies by where they headquarter, source, build, and sell, and the result, per The Quantum Insider’s account, was “complicated, deeply connected, and does not respect national borders.”

Alliance management. Finland, the Netherlands, the UK, Australia, Austria, Switzerland, France, Germany, Canada, Israel, Japan: these are the countries whose scientists, engineers, and companies have contributed to the capabilities that American quantum companies integrate and deploy. Dabbar’s framing, probably unintentionally, erases those contributions. When the U.S. asks allies to align export controls and coordinate on supply chain resilience, the ask is stronger if it acknowledges shared ownership of the stack rather than claiming sole credit for building it.

This connects directly to the argument I have made in Quantum Sovereignty, where I map quantum supply chain dependencies across 12 categories of enabling technology and more than 30 countries: quantum technology sovereignty requires understanding which capabilities you have, which you share with trusted allies, and which you depend on from sources that may not be reliable.

The China question. China has built growing parallel domestic implementation and supply chain capacity, particularly in quantum communications and photonics, even though its underlying scientific lineage, like every country’s, is international. Unlike allies whose research flows into and out of U.S. labs through academic exchange and commercial partnerships, China’s domestic implementation capacity operates with growing independence. The export control and technology-sharing implications follow: allies contributed to a shared stack, and maintaining access and interoperability serves everyone’s interests.

CRQC timeline implications. If you believe only one country has all the pieces needed to build a cryptographically relevant quantum computer, your Q-Day estimate depends on that country’s internal progress. If you recognize that the enabling capabilities are distributed across many nations, then the CRQC timeline depends on who can integrate across those sources. Distributed enabling technologies make national capability harder to infer from domestic hardware roadmaps alone, while also complicating component-level export-control strategies. This makes the CRQC Quantum Capability Framework‘s multi-dimensional tracking approach more important than single-country roadmap analysis.

What America Actually Built

The United States did not build every scientific and technical component of the quantum stack. Nor did any other country. Modern quantum technology emerged from a century of research distributed across American, British, Soviet and Russian, Canadian, European, Japanese, Australian, and Chinese institutions. America’s distinctive strength has been broader than invention alone: foundational research, talent attraction, federal laboratories, capital formation, standard-setting, systems engineering, and commercial scaling. That is an extraordinary achievement. It is not the same as sole authorship.

What the current quantum policy mobilization (the executive orders, the CHIPS Act investments, the planned Anderon foundry, the 2028 fault-tolerant target) is designed to maintain is something real and hard-won: the most effective system for integrating internationally originated science into deployed commercial technology. I support those investments. They are the right response to a real set of dependencies.

But the story you tell about why you are making those investments matters, because it shapes what you invest in next. “We are defending an inheritance we built alone” leads to a different investment profile than “we are maintaining an integration advantage that depends on allied contributions and supply chain access we do not fully control.” The second story is less satisfying at a summit podium. It is also true. And it produces better policy.

The U.S. quantum community, from conference stages to private boardrooms, keeps telling itself it built the whole stack. It should stop. The scientific stack was built internationally; the trusted industrial stack is heavily allied and interdependent. Understanding who built what is the beginning of understanding what you need to protect.