Rather than securing Europe, NATO enlargement1 has provoked a multifaceted backlash: a resurgent and militarized Russia, deep fissures within the NATO alliance itself, and a strategic convergence between Russia and China. As a result, trust across the transatlantic alliance is waning, while the specter of a broader European―or even global war―looms ever larger.

The pressing need today is not just to end the war in Ukraine but to reassess the entire structure of European security2. This requires rebuilding a credible multilateral framework that includes the United States, Europe, Russia, as well as China. Only through dialogue and compromise can the world escape the escalating spiral of mistrust, arms racing, and brinkman&womanship.

Cold Warriors had understood the dangers of expanding NATO. In 1997, a coalition3 of 50 former senior U.S. officials, diplomats, academics, and high-level retired military leaders issued an open letter to President Bill Clinton warning against NATO expansion. They argued that Russia posed no imminent threat, that Central and Eastern Europe were not under danger of invasion, and that NATO enlargement was “neither necessary nor desirable.”

Rather than advancing NATO toward Russia’s borders, they urged the strengthening of the Partnership for Peace (PfP)—a framework that included Russia and promoted mutual cooperation as an option to NATO enlargement and that was backed by high-ranking US military leaders such as NATO Supreme Allied Commanders Andrew Goodpaster, Jack Galvin, and John Shalikashvili, as well as Defense Secretary William Perry, as well as Cold Warrior Paul Nitze.

These leaders called for deeper arms reduction agreements, economic integration through the EU (which would have necessitated European cooperation with Moscow), and the creation of a broader cooperative security structure that included Russia, Europe, and the U.S. Their vision offered a more stable and inclusive path toward European security.

Unfortunately, their advice was ignored.

The strategic blunder of enlargement

Rather than heed the 1997 warnings, the Clinton administration pushed forward with NATO expansion. Driven by political lobbying from ethnic communities of eastern European origin in the U.S., strategic hawks like Anthony Lake and Richard Holbrooke, and US defense industry interests (notably Lockheed Martin), NATO moved to admit Poland, Hungary, and the Czech Republic in 1999.

This first wave of enlargement set the precedent for future expansions―Ukraine’s membership was urged by Clinton administration officials in mid-1994, if not earlier. The then-secret US government goal was to ultimately push NATO’s borders up to Russia’s doorstep.

Such actions directly contradicted the assurances given to Soviet leader Mikhail Gorbachev during German reunification talks—that NATO would not expand “one inch eastward.” By breaking this verbal commitment, the US and Europeans would not only alienate Russian reformers like Gorbachev and Yeltsin, but they would also embolden Russian hardliners. Over time, Moscow began to reorient its foreign policy toward strategic alignment with Beijing, culminating in their 2001 and 2022 “no limits” strategic partnerships.

The lost opportunity for a neutral Germany and neutral Ukraine

During the Cold War era, Washington, more or less reluctantly, had accepted the neutrality of Finland, Sweden, and Austria, and considered the possibility of a neutral Germany. In 1949, George Kennan proposed the option of a neutral, non-nuclear Germany that, he hoped, would have de-escalated East-West tensions. But this option was never pursued.

By 1989, Germany was unified within NATO’s nuclear aegis after Gorbachev reluctantly agreed to US and European oral assurances that NATO would not expand “one inch” eastward—a promise that was later broken after the Soviet Union collapsed in 1991. And although the Soviet Union collapsed in a relatively peaceful whimper and not a nuclear bang, the 1990-94 Russia-Ukraine “divorce” was never civilized. The territorial disputes between Russia and Ukraine did not come to an end even after Kyiv agreed to give up its nuclear weapons capabilities left over from the Soviet empire in 1994—but only after being pressed by Washington, which promised financial assistance, and by Russia, which threatened preemptive strikes.

A robust PfP, with mutual US-European-Russian security guarantees, including neutral PfP troop deployments, much as was the case with peacekeeping deployments in Bosnia after the 1990-95 war, would have offered a stronger system of cooperative collective security for Ukraine than did the 1994 Budapest Memorandum that only gave Ukraine weak US-UK-Russia-China-French security assurances. Stronger security guarantees would have been possible if Moscow had played a substantial role in framing the new security order in coordination with the US and Europeans. Had NATO built a robust, formally neutral, and non-nuclear Ukraine under the Partnership for Peace framework—with mutual guarantees and Russian consent—many of the ongoing disputes over Crimea, Donbass, the Sea of Azov, and broader Ukrainian territorial integrity might have been resolved diplomatically.

Yet, as Kyiv and Moscow never really concluded their uncivilized “divorce settlement,” the US decision to promise NATO membership for Ukraine in 2008 at the NATO Bucharest summit, without emphasizing the need for compromise over Crimea and the Donbas region, only served to exacerbate tensions. Instead of working to formally implement a neutral and non-nuclear Ukraine, the US continued to press secretly, and then more overtly, for NATO enlargement that would accordingly make Ukraine a member of a nuclear alliance. It is important to note that France and Germany had opposed the US decision to enlarge NATO in 2008, but did not veto it in deference to George W. Bush.

Moscow viewed these moves in support of NATO enlargement and Ukraine as direct threats, fueling President Putin’s rationale for the annexation of Crimea in 2014 and the full-scale invasion of Ukraine in 2022.

NATO’s internal fracturing

Contrary to strengthening transatlantic unity, NATO enlargement has contributed to its political fragmentation. Cold Warriors had warned that increasing NATO’s membership would dilute its cohesion. During the Cold War, NATO's unity was grounded in a shared perception of threat and strategic interdependence. In the post-Cold War period, however, with diverging national interests and historical grievances among new members, NATO has struggled to act cohesively in crises.

The 1999 Kosovo War, conducted without UN authorization and with limited consensus within NATO, marked the beginning of this fracturing as the Allies did not fully support NATO’s actions.

For its part, Russia interpreted NATO’s air war “over” Kosovo as evidence of US and European aggression versus Serbia, as a Russian and Chinese ally, rather than a humanitarian intervention intended to protect both Albanian and Serb Kosovars by placing peacekeepers on the ground.

NATO’s air war “over” Kosovo was consequently perceived in Moscow as a betrayal of the 1997 NATO-Russia Founding Act, which had promised non-aggression and partnership. Instead, NATO appeared to act as an interventionist force outside international law, cementing Russian perceptions of the alliance as a threat: Russian proposals to deal with the Kosovo conflict were simply ignored by an arrogant Clinton administration.

Irredentism and the Article V dilemma

NATO enlargement also exposed the alliance to internal border disputes and historic grievances—problems NATO was never designed to address. Irredentist claims linger across the region: between Russia and Ukraine, between the Baltic states, Finland and Russia, between Romania, Hungary, and Ukraine, between Poland and Belarus, in addition to those between NATO members, Turkey and Greece.

Article V, the collective defense clause, becomes dangerously ambiguous when applied to such regions. Would the U.S. risk nuclear war to defend cities like Riga or Warsaw over a localized conflict, even if Russia may be believed to be backing one side, as was the case for the Donbass conflict in Ukraine? Such questions challenge the credibility and unity of NATO.

Escalation: from expansion to war

The 2004 NATO expansion to the Baltic states (after Poland joined NATO in 1999) pressed both Sweden and Finland closer to NATO, once Moscow took military countermeasures to defend Kaliningrad. The 2008 Bucharest Summit promise of NATO membership to Ukraine and Georgia was later seen by Moscow as an existential threat.

These actions, combined with U.S. missile defense deployments and EU outreach to Ukraine, pushed Russia toward an increasingly aggressive posture. Russia’s 2014 annexation of Crimea, its support for “autonomists” in Donbass―that became “separatists” after the failure of the Normandy talks between Russia, Ukraine, France and Germany―and its full-scale invasion in 2022 are all part of a broader strategy to resist NATO's encroachment and maintain regional influence.

The collapse of arms control

Perhaps the most alarming consequence of NATO expansion and deteriorating relations with Russia has been the collapse of arms control. In addition to withdrawing from the ABM treaty, the U.S. withdrew from the INF Treaty in 2019, in response to Russian violations and China's missile deployments. The US is now deploying short and intermediate-range missile systems in Guam and the Philippines to deter China and North Korea. The START Treaty, which limits strategic nuclear weapons, is set to expire in 2026 with no clear path to renewal.

In late 2024, as the Ukraine war escalated, Russia launched a hypersonic missile strike on Dnipro using a new six-warhead system, following Ukraine’s use of US ATACMS missiles on Russian territory—breaking another Russian “red line.”

In response in upping the ante, the US and Germany plan to deploy intermediate-range missiles in Europe by 2026, including Tomahawk, SM-6, and Dark Eagle systems. German Chancellor Merz is shifting away from Scholz’s caution to an offensive support for Ukraine, including the potential deployment of Taurus cruise missiles, while deploying troops in NATO member Lithuania.

France has committed nuclear-capable Rafale jets to Germany and signed a mutual defense pact with Poland, which is ramping defense spending to 4.7% of GDP. French President Macron has floated the idea of expanding France’s nuclear umbrella to eastern Europe. However, this raises the risk of a nuclear "Maginot Line," vulnerable in today’s world of cyber, drone, and hybrid threats.

A European-made missile system, ELSA, is in development. This sets the stage for a potential Euro-Indo-Pacific missile crisis, more dangerous than the 1980s NATO-Soviet standoff.

Strategic fears and NATO expansion fallout

Moscow views NATO’s eastward expansion—especially Sweden and Finland’s 2024 accession—as deeply threatening.

On the one hand, Moscow sees the West backing a "Baltic-Black Sea alliance" and fears being encircled and dismembered, recalling historical efforts to weaken it as during the mid-19th-century Crimean War, much as Karl Marx advocated4 at the time.

On the other hand, Western super-hawks fear Russia could destabilize eastern Europe, foment unrest among ethnic Russians in Lithuania, Latvia, Estonia, Transnistria, and elsewhere, or attempt territorial expansion toward Odessa and Kyiv.

However, many of these tensions stem from non-military issues that require diplomacy, not further militarization.

Trump: North American imperialism

Much like Ronald Reagan’s Star Wars, Trump is promising yet another boondoggle, the Golden Dome, to defend against missile attacks from the Arctic. Assuming the US can really hide behind a missile defense shield, which appears dubious in the new era of hybrid and drone warfare, the Golden Dome raises Russian and Chinese fears that the US is seeking a first-strike capability.

Trump has raised historical US irredentist claims to NATO member Canada and to the control of Greenland, which is presently a self-governing territory of NATO member Denmark unless it opts for independence. How Trump will manipulate these irredentist claims to gain geopolitical influence and critical and rare earth minerals remains to be seen.

Trump's demands to augment defense spending—surpassing $1 trillion—may further undercut diplomatic and developmental strategies, limiting US soft power.

Strategic realignment and Sino-Russian cooperation

Rather than isolating Russia, NATO enlargement has pushed Moscow closer to Beijing. The collapse of arms treaties has triggered a new missile race. Beijing and Moscow now share military technologies, conduct joint exercises, and align diplomatically against what they view as American hegemonic overreach. This new axis complicates US and European security strategies, not only in Europe but across the Indo-Pacific as Beijing continues to pressure Taiwan in an effort to force Taipei to accept unification on Beijing’s terms. Here, the US needs to engage in full-fledged diplomacy so as to prevent a clash with China5 by finding a compromise with Beijing with respect to Taiwan.

The Suwalki gap and the danger of escalation

One of the most strategically vulnerable areas in Europe is the Suwalki Gap—a narrow strip of land between Poland and Lithuania that connects Kaliningrad with Belarus. Any military clash in this corridor could quickly escalate into a full-blown NATO-Russia conflict.

As Sweden and Finland have entered NATO, Moscow has opposed NATO’s surveillance of critical Russian military sites, especially with respect to Murmansk. As military deployments on both sides increase in the region and as both sides engage in acts of cyber sabotage, the risks of miscalculation are enhanced.

European proposals for a new “coalition of the willing” in Europe that could possibly involve deployments of as many as 10,000 troops in Ukraine, once and if a ceasefire is reached, must avoid triggering Russian escalation. Even if deployed far from the front lines, such European deployments should occur only with Russian consent and UN authorization. Otherwise, these forces risk worsening the conflict rather than containing it.

Undoing the damage: toward a new security framework

The risk of a broader conflict is real. The current trajectory—escalating arms races, mutual distrust, fragmented alliances—echoes the conditions that led to both World War I and World War II, which are now magnified by nuclear weapons, cyber warfare, and sophisticated drones.

Europe is teetering on the edge of a new partition. Militarized borders, the growing likelihood of conventional, unconventional, and nuclear escalation, and global economic fragmentation, coupled with the formation of geopolitical fault lines—from Ukraine to Kaliningrad to Taiwan and the South China Sea—are creating a volatile landscape. With real risks of conflict between NATO and Russia, between the U.S. and Iran, and between the US and China, the Trump administration’s efforts to de-escalate the Ukraine war and improve ties with Moscow are urgent.

Without renewed diplomatic effort, confidence-building, and restraint, we are entering a world where major power war is no longer unthinkable. Yet, while Trump aims for compromise, his foreign policy is clashing with European allies like the UK, France, Germany, Poland, and Ukraine, who fear he is “appeasing” Russia, drawing false historical parallels to Chamberlain’s failure with Hitler in the 1930s.

Concurrently, the role of China as a potential peacemaker is being ignored. Having mediated between Iran and Saudi Arabia, Beijing could play a similar role in Europe. Beijing’s interests in the Polar Silk Road and regional stability make it a natural stakeholder. The West should engage China as a co-mediator rather than treat it as an adversary. Instead of a conflict point, Kaliningrad could become a trade hub between Europe and the Eurasian Polar Silk Road.

It is still possible to chart a new path. But doing so requires the West to abandon maximalist positions and re-embrace diplomacy. This means:

  • Negotiating a new European security pact that includes the U.S., Europe, Russia, and China, while likewise working with Beijing to resolve the Taiwan and South China Seas disputes.

  • Rebuilding arms control frameworks to reduce nuclear, conventional, drone, and cyber threats.

  • Promoting a neutral, non-nuclear Ukraine as a bridge state between Europe, Russia and Eurasia.

  • Phased sanctions relief for Russia, tied to verifiable de-escalation steps.

  • Joint and international ventures in agriculture, raw materials, and energy in Ukraine and the Black Sea areas with Russia, Ukraine, Europe, and the U.S.

  • Resolving regional political-economic disputes over Russian-held Kaliningrad and between Poland and Belarus, between the Baltic states, Finland and Russia, not to overlook disputes between Romania, Hungary, Moldova and Ukraine…

  • International peacekeeping deployments throughout Ukraine and Eastern Europe in a revived PfP, led by neutral countries like India, Brazil, and possibly NATO members Hungary and Turkey.

A realistic settlement may require Kyiv to accept de facto Russian control over Crimea and parts of the Donbass, without formal recognition, to end the war. This would be painful, but necessary to stop further bloodshed. At the same time, future negotiations could possibly seek joint sovereignty measures over certain regions, for example.

Averting World War Trump

The critics of NATO enlargement were right. What was sold as a strategy for peace has instead sown division, war, and instability. By ignoring the wisdom of Cold War veterans, the US and Europeans missed a vital opportunity to build a truly inclusive and cooperative security order. The ghosts of ignored advice from the Cold War generation should have served not just as a warning but also as a roadmap for rebuilding trust and lasting security.

Without bold diplomacy, strategic restraint, and multilateral cooperation, the world risks sliding into a new era of catastrophic conflict. Averting another major power war depends on diplomacy over escalation, compromise over maximalism, and multilateral coordination over unilateral action.

There will be no regional or global peace unless key players work together: the U.S., Europe, Russia, China, among other neutral nations. It is not too late to change course. But doing so requires the humility to admit past mistakes—and the courage to pursue peace over power.

This article was based on my talk at the Peace Roundtable 17, American University in Moscow.

References

1 Time to Undo the Damage, The Relevance of Cold Warrior Opposition to NATO Enlargement, by Hall Gardner.
2 Ibid.
3 Opposition to NATO Expansion, Arms Control Association.
4 Karl Marx and NATO, Meer.
5 The Coming Clash With China by Hall Gardner.