Military spending is up, plans to counter a potential Russian attack have been upgraded and NATO has added two new members to fortify an alliance now considered at its strongest in decades.

But when President Joe Biden welcomes heads of state for a Washington summit next week, jitters about the future will likely dominate the backroom talk as allies contemplate how to “Trump-proof” NATO.

“It’s a paradoxical moment where we have this organization that is arguably stronger than ever, at least stronger than any time since the end of the Cold War. And yet American involvement in it, American commitment, is potentially at risk,” said John R. Deni, a NATO expert with the U.S. Army War College’s Strategic Studies Institute.

At the summit, there will be pronouncements about the durability of an organization touted by its members as the most successful military alliance in history. And leaders are expected to approve several new measures during the three-day gathering aimed at further bolstering defenses, enhancing support for Ukraine’s military and extending a “bridge” to eventual NATO membership for Kyiv.

“Our most urgent task at the summit will be support to Ukraine. Ukraine must prevail, and they need our sustained support,” Secretary-General Jens Stoltenberg told reporters Friday at his Brussels headquarters.

But beyond the summit agenda, NATO stands on shaky ground.

Angst in some European capitals over the potential return of Donald Trump to the White House looms over events.

The unease intensified after a dismal Biden debate performance last week, which was reflected in a New York Times/Siena poll released this week that gave former president Trump a three-percentage point bump.

Should Trump return, the strength of the U.S. commitment to NATO is open to debate, given Trump’s long held skepticism about the value of an alliance he characterizes as a collection of security freeloaders.

Other political events in Europe, such as the rise of Marine Le Pen’s far-right NATO-skeptic party in recent French elections, point to a turbulent future for an alliance founded in the aftermath of World War II.

“(T)he almost one billion people protected by the alliance stand at a precipice of danger … If Donald Trump and Marie Le Pen are elected, they will end NATO,” said Jorge Benitez, an expert on NATO and European security with the Washington-based Atlantic Council.

While Trump has had harsh words for NATO, he hasn’t spelled out his intentions in a possible second term. Even without attempting to pull out of NATO, the alliance could be compromised if the United States indicated that it wasn’t fully on board with NATO’s linchpin Article 5 provision that an attack on one is an attack on all.

Regardless, Trump’s ambivalence about the alliance and opposition to one of its key campaigns — training and arming the Ukrainian military in its war with Russia — has allies looking at other options.

To that end, the Washington summit is expected to shake up how allies get weaponry to Ukraine, with NATO taking command of an effort that so far has been a U.S.-led endeavor carried out from the Army’s European headquarters in Wiesbaden, Germany.

The new NATO-led effort would remain in Wiesbaden but be comprised of a larger multinational staff that reports to NATO’s top commander, U.S. Army Gen. Christopher Cavoli.

While NATO hasn’t called the shift a move to counter Trump, it’s nonetheless been described by alliance observers as an attempt to Trump-proof allied support for Ukraine should America back out in the future.

Stoltenberg, asked Friday about concerns over the longevity of efforts to support Ukraine and other initiatives amid political upheaval in various member countries, said he was confident the alliance will hold together.

“I cannot guarantee. NATO has never been a given. NATO will never be a given. But NATO has proven extremely resilient,” Stoltenberg said.

But skeptics say such Trump-proofing ignores the central role the U.S. plays almost across the board inside NATO when it comes to carrying out important missions.

“It could be difficult for NATO to make up for what the Americans bring to the table,” Deni said.

The U.S. military serves as the backbone of an allied logistics system that is at the heart of the effort to get arms to the Ukrainians, Deni said.

National security analysts in Trump’s orbit also have already made clear that a major military shift to the Pacific is in order, and that would mean fewer American troops in Europe.

But the ability of Europeans to carry the security load in Europe — both on supporting Ukraine and executing its own defense plans — appears to be years away.

In the case of arming the Ukrainians, allies are making progress as they ramp up their defense industrial base and could be in a position to carry the bulk of the burden in a year or two, Deni said.

But when it comes to filling the requirements of NATO’s own territorial defense plans, the Europeans are far from ready to do it on their own, he said.

“Certainly, in terms of manpower alone, even the most aggressive of our European allies on this front like the Poles, who are on their way (to building the largest European army in NATO) will take years to do it,” Deni said.

In Washington, allies are expected to fine-tune defense plans and a new force model that puts hundreds of thousands of allied troops on a higher state of alert. Considering the central role of the U.S. military in Europe, American troops would be a major part of any NATO territorial defense strategy.

Possibly by the end of the decade, the Polish army might be capable of stepping up in some of the ways American units currently do, Deni said.

Besides overhauling how NATO trains and equips Ukraine’s military, the question of the country’s future membership in the alliance is on the NATO summit agenda. Leaders have said repeatedly that Kyiv’s future is in NATO, but there is no consensus in the alliance about when that should happen.

In Washington, allies will agree to more concrete language on Ukraine’s pathway.

However, it’s not at all clear if there would ever be consensus within NATO to take the next step and invite Ukraine even after its war ends with Russia.

Critics of the idea say the move would be an unnecessary escalation with Moscow and put allies on the hook for coming to Ukraine’s defense should fighting break out again.

But others say failure to extend a membership invitation in Washington adds up to a summit that falls short of expectations.

“No steps or pathways to NATO membership will be real and concrete until Biden and (German Chancellor Olaf) Scholz agree to begin the membership process for Ukraine,” Benitez said. “Everything short of that will be just more empty promises that do not help the people of Ukraine and that do not deter further aggression from Russia.”

With 32 allies, there are bound to be disputes around the table in Washington. But allies can point to progress in one area that has been a point of contention among members for many years.

Stoltenberg said 23 of NATO’s 32 members now spend at least 2% of gross domestic product on their respective militaries, a NATO benchmark met by only three allies a decade ago.

“Defense spending across European allies and Canada is up 18% this year alone, the biggest increase in decades. Allies are taking burden-sharing seriously,” Stoltenberg said.

Failure among members to hit 2% has been at the center of U.S. NATO critiques for decades, spanning across administrations. Trump took those criticisms to another level, with tough talk that broke with diplomatic norms.

In Washington, leaders can be expected to talk up the progress during the highly choreographed gathering, where the main goal will be avoiding signs of discord among members.

“Really the most vital part of any NATO summit is to portray unity,” Deni said. “The key is that we emerge at the end without a lot of strife and with unity at the center of what the alliance is up to.”

previous coverage

• NATO will strive to project unity at Washington summit, but cracks emerge
• Incoming NATO leader seen as steady hand who can work with US, regardless of election outcome