NATO faces unprecedented strain amid US-Iran tensions and Trump’s threats

The ongoing conflict in Iran has intensified divisions within NATO, as President Donald Trump criticized allies for not supporting his military actions. This week, Trump labeled their lack of backing a "stain on the alliance that will never disappear." German Chancellor Friedrich Merz described the situation as a "trans-Atlantic stress test," highlighting the fragility of the alliance.

Analysts warn that NATO's future is uncertain, particularly if the US were to withdraw. Jim Townsend, an adjunct senior fellow at the Center for a New American Security, stated, "We are closer to a break than we have ever been." While Trump cannot unilaterally withdraw the US from NATO, he can undermine it by threatening to reduce American military support and troop presence in Europe. The Wall Street Journal reported that Trump is considering relocating US bases from countries that did not support the Iran war to more favorable nations.

Despite these challenges, European allies are not entirely powerless. The Russian invasion of Ukraine has underscored their reliance on US military capabilities, prompting a significant increase in defense spending—over 62 percent from 2020 to 2025. However, experts note that Europe still faces considerable gaps in military capabilities, particularly in areas such as deep strike capabilities and integrated air defense.

Some analysts, like Minna Alander from the Stockholm Centre for Eastern European Studies, believe that NATO could survive a US withdrawal, as European members may seek to maintain the alliance in a different form. However, the timeline for addressing these vulnerabilities is tight, with estimates suggesting that Russia could pose a threat to NATO territory as early as 2027.

What to watch: The upcoming decisions by European nations regarding defense spending and military cooperation will be critical in determining NATO's resilience amid US uncertainties.