The Republic is a journal published by The Palantir Foundation, featuring commentary and essays on technology, national security policy, and international affairs.

Deterrence Deferred. For Now.

Jan Matejko’s Constitution of May 3, 1791 (1891) depicts the last attempt at reforming the institutions of the Polish-Lithuanian Commonwealth. Unfortunately, the reforms came too late, and within a year, Russia invaded. Within four years, the Commonwealth ceased to exist.

Deterrence Deferred. For Now.

Europe is running out of time to avoid the fate of the Polish-Lithuanian Commonwealth.

By ,

Barna Peterfi is a visiting research fellow at the Yorktown Institute and an Andrassy National Security Fellow.

Thomas Hollands is a public affairs professional based in Brussels, with a research background spanning digital infrastructure and European defence. He holds degrees from the Brussels School of Governance and the University of Edinburgh.

The late eighteenth century marked a period of political and institutional crisis for the Polish–Lithuanian Commonwealth. Having once been the largest state in Europe, stretching from the Baltic to Eastern Ukraine, the Commonwealth had been withering away for decades. Many point to the institutional gridlock caused by the liberum veto as the source of this decay, which was the right of any single deputy in the Sejm (the Commonwealth’s parliament) to dissolve the entire parliamentary session, as well as nullify any legislation already passed in that session. As a consequence of that, roughly a third of all Sejm sessions between 1573 and 1763 failed to pass any legislation.1

Under Augustus III (1733-1763), the paralysis arguably reached its peak, with only one session from approximately fifteen during his thirty-year reign producing any substantive legislation. That level of legislative stagnation is comparable to the U.S. Congress passing almost no substantive legislation from the late 1990s to the present day. Before this period of dysfunction, however, the Commonwealth’s battlefield successes such as the battles of Kircholm (1605) against the Swedish and Chocim (1673) against the Ottomans lent it a credible deterrent posture in the region.2 Nevertheless, the institution of the liberum veto, “the sinister symbol of old Polish anarchy,” proved to have disastrous consequences for the Commonwealth’s overall security architecture.3 The state’s inability to pass tax or military legislation led to the contraction of its army while those of its neighbors expanded, which directly contributed to the erosion of the Commonwealth’s deterrence capabilities that had previously ensured its security.4

Missed Opportunity

For all its dysfunction, the Commonwealth was not without a moment of opportunity. In 1683, King John III Sobieski (1674-1696) led the largest cavalry charge in recorded history down from the Kahlenberg heights, breaking the Ottoman siege of Vienna. The charge comprised approximately 18,000 horsemen, including 3,000 of the famed Winged Hussars.5 Sobieski’s victory at Vienna uniquely positioned him to modernize the Commonwealth’s military and consolidate regional power by leveraging the political capital gained from such a victorious battle. He had won the support of neighboring European leaders and the Pope, whose assent was needed to push through such fundamental reforms.

Sobieski tried to seize his window of opportunity to fund a professional standing force similar to the Commonwealth’s neighbors in the region, but the Sejm blocked every attempt. Half the sessions during his reign were dissolved by the veto of magnate factions.6 Sobieski failed.

Just a few decades later, Russia took advantage of the Commonwealth’s military weakness to invade and occupy the nation. At the “Silent Sejm” of 1717, so named because no debate was permitted and only pre-written resolutions were read aloud, Russian troops watched on.7 The Russian army encircled Warsaw Castle to ensure compliance. The Silent Sejm agreed to cap the Commonwealth’s standing army at 24,000 men. Comparatively, neighboring Russia maintained 300,000 troops, whilst Prussia and Austria each fielded between 150,000 and 200,000. In practice, the Commonwealth’s army soon fell below even that relatively humble ceiling.

It is important to note that the military deterioration was not just a matter of size but also type, reflecting an issue that today would be described as a “technology gap.” The Commonwealth was stuck in a previous era’s military paradigm. The Winged Hussars were rendered obsolete not only by the lack of political reforms but also by the improved firearms and professional infantry doctrine that swept across the rest of Europe.

The reformers’ last stand came with the Constitution of May 3, 1791, the first modern codified constitution in Europe. Among other reforms, the new Constitution abolished the liberum veto, established majority rule, and mandated a professional standing army of 100,000 men. Edmund Burke praised it as “probably the most pure and defecated [i.e., altruistic] public good which ever has been conferred on mankind.”8 But these reforms, which would have modernized the Commonwealth’s security architecture and deterrence capabilities, were too little too late.

When Russia invaded in May 1792, less than 40,000 of the planned 100,000 soldiers had been assembled. That invasion led to the Third Partition, which erased the Commonwealth from the map entirely. Neither Poland nor Lithuania would re-emerge as independent states until 1918, and then only because WWI simultaneously destroyed all three partitioning empires.9

The Commonwealth’s history serves as an early example of how regional and federal interests can conflict and often undermine each other, complicating efficiency and power projection while making the state machinery increasingly dysfunctional.

From Warsaw to Brussels

The Polish-Lithuanian Commonwealth and the European Union share not just a common threat environment but also a common institutional DNA. Both are large, diverse, multinational political systems in which diverging national interests complicate collective action and where no common defense architecture has ever functioned at the speed the external environment demands. Institutional paralysis, external dependency, and recurring failures to modernize are structural features, and their consequences have historically been the same: eroded deterrence and strategic vulnerability.

Importantly, the EU was never intended to operate with a start-up-like mindset. It is a deliberately deliberative institution, built on rigorously logical procedures, consensus, and compromise. For much of its history, these were features rather than flaws. However, we must recognize that the threat environment has evolved faster than the institution, creating a gap that is becoming increasingly difficult to manage.

Just as the Commonwealth found itself increasingly encircled in the late eighteenth century, Europe today faces a geopolitical environment that has deteriorated rapidly. We face a full-scale war in Ukraine, the risk of intensifying continental conflict with Russia, an unstable Iranian regime possessing missiles capable of reaching European cities, a fracturing trans-Atlantic alliance, and accelerating global competition over technological and industrial sovereignty.10 All of this comes in a time when the EU confronts an annual investment gap of roughly 750–800 billion euros, approximately 4.5 percent of GDP.11

Nonetheless, much like the Commonwealth in the aftermath of Vienna, the EU is at a rare moment of strategic opportunity: the threat environment is clear, public backing is increasing, and the case for a credible, modernized defense and security architecture is the strongest it has been in decades.

For that, however, the Old Continent must first do what the Commonwealth’s reformers did in 1791 and acknowledge reality plainly. Europe’s defense capabilities are underfunded, institutionally fragmented, disjointed in procedure, and still organized around the strategic assumptions of a previous era. We are fielding Winged Hussars on a battlefield that has been transformed.

The numbers bear this out. Although some Member States have begun to outspend the U.S. as a share of GDP, the EU’s defense spending remains roughly half that of the U.S. The problem, however, runs deeper than resources alone. Europe’s military landscape is dangerously fragmented. As examples, it fields 178 major weapon systems compared to just 30 in the U.S., 17 types of main battle tanks versus 1, and 20 fighter aircraft types against Washington’s 6.12 This lack of standardization undermines interoperability and slows adaptation in a time when agility increasingly matters more than mass. As the war in Ukraine has shown, “military advantage is migrating from what a force possesses to how fast it can learn.”13 In the new era of war, combat power quickly erodes in the absence of institutional agility.

Addressing these gaps demands structural change. A European single market for defense with its own reformed policymaking process — that respects member state rights but also consolidates fragmented procurement procedures — is becoming a strategic necessity.

The Institutional Kill Zone

Notably, Europe has what it needs to build a credible and adaptive defense-technology base. Europe has always had the engineers and capital. It can now couple these resources with the threat clarity and public backing that come from a land war on its borders and an increasingly unstable environment globally.

Ukraine showed Member States how battlefield agility and software-enabled adaptation can offset advantage derived from mass. Ukrainian low-cost Unmanned Aircraft Systems (UAS) production surged from a few thousand units in 2022 to over two million of all types in 2024. Software-defined FPV drones accounted for an estimated 80 percent of Russian battlefield casualties in 2025.14

Although European governments remain primarily focused on replenishing weapons stocks and improving near-term readiness, the lessons of Ukrainian capability development are beginning to spill across the border. A growing defense-tech startup ecosystem is emerging across the continent as a result. Venture capital in the sector grew over 500 percent between 2021 and 2024, making it Europe’s fastest-growing VC segment.15 In the first half of 2025 alone, European defense startups attracted €946 million in venture capital — an increase of 26 percent in contrast to the same period of the year before.

This surge in private capital is narrowing the deal flow and investment gap between the EU and the U.S. However, the EU lacks an institutional architecture capable of moving at the speed the moment demands. Political will and capital, as the Commonwealth’s history shows, are necessary but not sufficient alone. Procurement timelines can stretch over a decade. National certification regimes fragment the market and funding cycles are mostly still calibrated for peacetime consensus. The result is what can only be called an institutional No Man’s Land.

Thus, European startups, unable to win contracts within the timeframes venture capital demands, face a choice between relocating to the U.S. or dying in Brussels’ procedural labyrinth. Importantly, the U.S. still captures 85 percent of all defense-technology venture funding among NATO allies.16 That is good for American deal flow, but undesirable for the alliance. As the Trump administration repeatedly made clear, Washington needs European allies who can field their own capabilities. Being permanent customers of American platforms worked out for Europe but is no longer enough. A more self-sufficient Europe affords the U.S. the strategic bandwidth to focus on other theaters without leaving NATO’s eastern flank exposed.

As the Commonwealth did in the 18th century, Europe faces a technology gap that cripples its military deterrence capabilities. Fixing the issue will require simplified regulations and a navigable legal environment allowing for rapid adaptation from industry and cross-border integration among operators. This would allow the EU to address a long-standing inability to effectively convert resources into technological advantage and military capability.

When the bloc pledged to deliver a million 155mm artillery shells to Ukraine within twelve months, only 524,000 arrived by the deadline.17 Just as the Commonwealth in 1792 could field less than 50 percent of the 100,000 troops its constitution demanded, Europe today has trouble translating political commitments into material reality at the speed its security environment requires.

A single market for European defense that consolidates supply chains and enables cross-border procurement at scale could reduce procedural inefficiencies, while saving member states an estimated €60–75 billion per year in the process.18 It would also give European primes and startups a navigable path through Brussels, and open the door to better integration of allied capabilities and access for allied innovators in a more coherent European market.

Sobieski’s Window Reopens

The Commonwealth’s reformers had the right ideas; they just lacked the time to build up their defense capabilities. They ran out of time because their state infrastructure had spent a century making itself incapable of acting on correct diagnoses. The European Project is confronted with a similar challenge. The Munich Security Report 2026 documented what it called a structural collapse of the rules-based order. Chancellor Merz acknowledged at the conference that great-power politics had returned and that Europe’s freedom was no longer a given.19

Coalitions of the willing have already emerged outside formal structures. Germany’s European Sky Shield Initiative now includes 24 countries.20 There are even discussions about Bruegel’s proposed European Defense Mechanism, which would issue bonds backed by willing EU and non-EU states.21 The new NATO target, agreed at the Hague Summit in June 2025, calls for members to spend five percent of GDP on defense and security by 2035. However, to translate these into material reality, Europe must pair its financial commitments with action to reform and modernize its regulatory environment that allows for consolidated procedures and mobilizes the continent’s defense industrial and technology base.

The Commonwealth’s history highlights the unique importance of tackling regulatory deficiencies in a constantly evolving threat environment. Europe is built on millennia-old debates, battles, and revolutions. In order for those debates to continue and thrive, the forum itself must be guarded. But if Europe is fighting with one gun and 27 different kinds of bullets, this European Project is in danger of following the path of the Polish-Lithuanian Commonwealth.

  1. Jacek Jędruch, Constitutions, Elections, and Legislatures of Poland, 1493–1993: A Guide to Their History (Washington, DC: University Press of America, 1982; rev. ed. New York: EJJ Books, 1998), 126–142. ↩︎
  2. Steven Thomas, “Army of the Polish‑Lithuanian Commonwealth in the 17th Century,” Balagan, August 1, 2020. ↩︎
  3. Piotr S. Wandycz, The Price of Freedom: A History of East Central Europe from the Middle Ages to the Present (London: Routledge, 2001), 103–104. ↩︎
  4. Mikołaj Dueholm, “With Fire and Sword: Military Factors in the Disintegration of the Polish‑Lithuanian Commonwealth,” UROP, advised by Professor Howard Louthan, August 28, 2021. ↩︎
  5. Norman Davies, God’s Playground: A History of Poland, vol. 1, The Origins to 1795 (New York: Columbia University Press, 2005), 325–328. ↩︎
  6. Jerzy Lukowski, Liberty’s Folly: The Polish-Lithuanian Commonwealth in the Eighteenth Century, 1697–1795 (London: Routledge, 1991), 3–15. ↩︎
  7. Daniel Stone, The Polish-Lithuanian State, 1386–1795 (Seattle: University of Washington Press, 2001), 248–252; Davies, God’s Playground, vol. 1, 377–380. ↩︎
  8. Edmund Burke, “An Appeal from the New to the Old Whigs” (1791), in The Writings and Speeches of Edmund Burke, vol. 4, ed. P.J. Marshall and Donald C. Bryant (Oxford: Oxford University Press, 2015), 464. ↩︎
  9. Lukowski, Partitions of Poland, 135–148; Paul W. Schroeder, The Transformation of European Politics 1763–1848 (Oxford: Oxford University Press, 1996), 105–112. ↩︎
  10. Samuel Charap and Hiski Haukkala, “Europe’s Next War: The Rising Risk of NATO-Russia Conflict,” Foreign Affairs 105, no. 2 (March/April 2026). ↩︎
  11. Mario Draghi, The Future of European Competitiveness (Brussels: European Commission, September 2024), 2–5. ↩︎
  12. Munich Security Conference / McKinsey & Company, European Defense Report (Munich: MSC, 2017; updated MSC Special Edition, 2023); cited in European Commission, European Defence Industrial Strategy (EDIS), 5 March 2024. Data vintage: 2017–2018. ↩︎
  13. Bryan Clark, Ian Crone, and Dan Patt, The Quick and the Dead: How Adaptation in Contact Drives Military Advantage (Washington, DC: Hudson Institute, March 2026). ↩︎
  14. President Zelenskyy, end-of-year address, December 2024 (2.2 million drones of all types); Atlantic Council, “Drone Superpower: Ukrainian Wartime Innovation Offers Lessons for NATO” (Washington, DC: Atlantic Council, 2025); ECFR, “Drones in Ukraine: Four Lessons for the West,” 10 January 2025. ↩︎
  15. McKinsey & Company, “European Defense Tech Start-ups: In It for the Long Run” (2025). The 500 percent figure compares total investment in 2021–2024 against the preceding three-year period (2018–2020). ↩︎
  16. Dealroom, The State of Defence Tech 2025 (Amsterdam: Dealroom, 2025). The 85 percent figure covers cumulative NATO-ally defence-tech VC since 2019. ↩︎
  17. Borrell, Josep. “EU Will Only Supply Half of Promised Shells to Ukraine by March.” Reuters, January 31, 2024. ↩︎
  18. European Parliamentary Research Service. “Improving the Quality of European Defence Spending: Cost of Non-Europe Report.” January 6, 2026. ↩︎
  19. Munich Security Conference, Munich Security Report 2026: Under Destruction, ed. Tobias Bunde and Sophie Eisentraut (Munich: MSC, February 2026), 18–24; speech by Chancellor Friedrich Merz, MSC, 13 February 2026. ↩︎
  20. Thomas Withington, “Connect-4,” European Security & Defence, June 11, 2025. ↩︎
  21. SWP Berlin, “Taming National Interests within the CFSP” (Berlin: SWP, 2024); UK Ministry of Defence, “Trinity House Agreement: First Major Milestones,” 15 May 2025; Bruegel, “The Governance and Funding of European Rearmament” (Brussels: Bruegel, 2025). ↩︎