Continuities and Unknowns: US NATO Policy in 2025 and Beyond

The future of transatlantic security policy is undetermined in this hot political summer. The Washington NATO summit was the concluding act of the political moment that started with Russia’s invasion of Ukraine. Much of what Kyiv has asked for in the past two years is being delivered, from ATACMS to F16s to Ukraine’s “irreversible” path to NATO. Allies are also putting money and industrial output toward defending “every inch” of territory. Even policy toward the People’s Republic of China (PRC) has leapt forward. NATO called the PRC a “decisive enabler of Russia’s war against Ukraine” and a “systemic challenge to Euro-Atlantic security.”

What comes next is less clear. The US election in November can lead to three outcomes: 

• Biden-administration policies of resolve and prudence continue under a Democratic successor. 
• A Trump-Vance administration tries to quickly end the war in Ukraine and makes greater spending demands on NATO allies. 
• A Democratic successor changes Biden-era approaches to European security, possibly introducing policies that are bolder than the Biden administration’s have been. 

In all scenarios, three US priorities will endure: increasing defense spending and capabilities, deterring Russia, and countering the PRC. 

Continuity on Defense-Spending Needs

Republicans still are focused on European defense spending. At the Republican National Convention (RNC), Republican vice-presidential candidate J.D. Vance called on the party to “make sure that our allies share in the burden of securing world peace. No more free rides for nations that betray the generosity of the American taxpayer.” The undertones of the word “betray” point to the heightened importance of this issue. If, as Vance seems to suggest, a lack of defense spending is tantamount to betrayal, then the inverse—more defense spending—would be a marker of loyalty. 

The Democrats have also demanded defense spending increases from European allies, and the fact that 23 of 32 NATO allies now spend more than 2% of their GDP on defense is a Biden administration achievement.

Deterring Russia                                                                          

President Biden and former President Trump both want to deter Russia. Biden made clear at the NATO Summit that he was going to be tough on Putin: “If we allow Russia to succeed in Ukraine, they’re not stopping at Ukraine.” Trump also is no fan of Russian aggression. At the RNC, Trump spoke angrily about “Russian warships and nuclear submarines … operating 60 miles off the coast in Cuba” and called Russia’s invasion of Ukraine a “horrible war.”

But there are likely to be differences between a Democratic candidate’s and Trump’s policies on Russia. Biden speaks out against Putin not only on behalf of Americans but also of the whole alliance, and a Democratic successor is likely to do the same. Conversely, Trump said in February that he would encourage Russia to do “whatever the hell they want” to any under-spending NATO country. In addition, Vance is hesitant on intervention, saying that “we will send our kids to war only when we must." He has demanded that Germany increase defense manufacturing, pushing more of the burden onto Europe. How a Trump-Vance administration would determine when the United States “must” intervene is an open question. 

Countering the PRC

Countering the PRC’s aggression will be Washington’s evergreen priority. Trump focused on the PRC at the RNC, expressing dismay that it is “circling Taiwan”. And Democrats are worried, too.

The Biden-era National Defense Strategy labeled the PRC the “pacing challenge” for the United States, and Biden argued in July that Xi must understand that “there’s a price to pay for undercutting both the Pacific Basin, as well as Europe, and as relates to Russia and dealing with Ukraine.” 

It is unlikely that the United States will turn away from Pacific needs to commit largely to European priorities. 

An Unknown Path on Ukraine

Ongoing support for Ukraine’s military and Ukraine’s NATO path is uncertain. Under a future Democrat—especially if Kamala Harris were to become president—Biden policies would likely continue. 

At the Munich Security Conference in February, Harris said, “President Joe Biden and I stand with Ukraine.... We will work to secure critical weapons and resources.” Whether the Democrats can deliver future aid will depend on Republican support in Congress. It is too early to say how the Democratic shake-up will affect Congressional races. 

On the Republican side, Trump seeks to quickly end the war. He may support Ukraine: he did not use his influence to block the spring supplemental package for Ukraine, and he had what he called a “very good phone call” with Volodymyr Zelenskyy in late July. 

Vance’s support for Ukraine may be weaker. In Munich, he asked “Can we send the level of weaponry we’ve sent for the last 18 months for the next 18 months? We simply cannot.” Instead, he sought “some negotiated peace”. If Europe wants Ukraine to have the resources necessary to fight, Vance may be a difficult person to deal with on the other side of the Atlantic.

What Europe Should Do

For Europe to protect itself and Ukraine against Russia, it will have to invest heavily its own defense capabilities. Focusing on a strong eastern flank will help ensure deterrence if the White House sends mixed signals about NATO. Investments in defense will also show a future Republican administration that Europe is a loyal partner. 

Support for Ukraine—financial, humanitarian, and military—will be essential. But even with a Democrat in the White House, Ukraine aid may be hard to pass in Congress. In a Republican administration, little aid may flow to Ukraine. 

Most difficult for Europe will be policy toward Beijing. Washington’s unwavering focus on the PRC suggests that Europe must also take a tough line on it to maintain its friendship with the White House.