The post–Cold War international order slowly withered for decades, but it reached a clear inflection point on June 1, 2025. On that day, Ukraine deployed less than a million dollars’ worth of hobby-shop technology to destroy Russian strategic bombers worth billions. Russia’s exquisite air defenses and geographic depth made no difference, and images of burning Russian bombers finally settled the debate as to whether drones are a tactical aberration or a tectonic shift in geopolitical power. Operation Spider’s Web, as the Ukrainian operation was named, codified the rules of the new era: bespoke platforms are luxury items and “mass”—the ability to employ more weapons faster and for a longer period—is essential.

This radical change necessitates continued reform in the United States’ defense ecosystem. As many have noted, the technological advances of private commercial firms are outpacing those made by traditional defense industries, artificial intelligence is accelerating innovation, and the wide diffusion of technology is blurring the capabilities of state and nonstate actors. Less appreciated, however, is how this new era is also changing the currencies of international statecraft. By transforming the application of violence and expanding warfare from limited conflicts to existential risks, this inflection point requires a new way of thinking about and constructing alliances.

Since the end of World War II, the United States’ greatest deterrence factor has been unified alliances whose combined military might is preeminent. But this allied might is only as dominant as the sum of the parts. As the war in Ukraine and conflict in the Middle East have demonstrated, many large militaries are not prepared for the current era of mass-produced precision strikes and interceptions. Defense industries are still structured around expensive, exquisite, and proprietary military platforms.

The United States’s strength depends on strong alliances, with a shared defense industrial base that can aggregate capabilities for a new era of warfare. To get there, Washington must encourage a free-market, international defense ecosystem defined by open architecture and industrial, software, and hardware compatibility. The United States’ greatest deterrent, the foundation of its diplomatic clout, and the primary factor in its ability to win on the modern battlefield this next century will be its collective allied industrial capacity and military interoperability. If it fails to secure such a strategy of compatibility, other state and nonstate actors will be meaningfully more likely to take escalatory actions.

Conceptually, the idea of interoperability and collective defense innovation is well trodden. But, practically, it has never come to fruition at scale. The global defense architecture is still oriented toward a Cold War–era industrial model. This model generally involves United States defense companies creating small batches of exquisite equipment that is operated with proprietary, siloed software. Allies would purchase this equipment and combine it with their own nation’s military offerings, wherever possible. Most companies were incentivized to create defensive moats around their products once they were sold to prevent competition from replacing them.

All this unfolded at a time of relative global peace, so the special interest decision-making model amplified the entrenchment of these companies and created a mosaic of military platforms and systems. The United States and its allies recognized the digital revolution of the past 20 years would require more compatibility, but they deferred to the momentum of their acquisition processes and chose to only tinker on the margins rather than embark on fundamental change.

This complacency led to the level of unpreparedness that U.S. President Donald Trump inherited last year. The U.S.-led defense architecture had successfully deterred large-scale conflict for decades, but the U.S. Army in 2025 looked shockingly similar to that of 1975. Because the incentive was to maintain the status quo rather than steer the future of warfare, the U.S. defense industry had devolved into an oligopoly. A handful of so-called prime contractors developed exquisite platforms with built-in firewalls and produced them in custom-built factories. Meanwhile, decades of government statutes and policies, along with poor acquisition incentives, optimized for job distribution over efficacy and ultimately encouraged contractors to make platforms that are expensive and slow to replace—in other words, the antithesis of affordable mass. Overregulation also paralyzed foreign military sales, and procedural and financial barriers to entry locked out small and medium-sized companies.

With all these same dynamics at play in other countries, U.S. allies each suffered from their own isolated oligopolies. The allied industrial base—and thus Washington’s ability to fight as a coalition—atrophied.

Contrast this dynamic with private technology companies, which are perpetually at war for their survival. Over the same time period, these companies have made advances that have driven humanity into the future. They race toward minimally viable products, tighter innovation cycles, and ever-evolving and improving offerings. And they pursue open data architectures to ensure their products meet industry standards to exchange data across the Internet. A smartphone that cannot exchange data, after all, is simply an expensive paperweight.

The U.S. Army in 2025 looked shockingly similar to that of 1975.

The stark divide between open and closed systems is something I witnessed firsthand earlier this year. At Grafenwoehr Training Area in Germany, I watched allied forces and Ukrainian forces test counterdrone capabilities in a combat scenario. The allied soldiers performed well in a scenario that mimicked previous conflicts with limited air threats, but their systems were not designed for the large drone swarms of modern combat. As the air threats were layered into the exercise, I watched an........

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