Since 2022, the United States and European Union have presented a largely united front in support of Ukraine. But a series of developments this year, including a divisive UN vote and a contentious Oval Office meeting between President Donald Trump and Ukrainian President Volodymyr Zelensky, has revealed widening cracks in the transatlantic alliance. Interviews with peace scholars at Notre Dame provided insight into why Europe is reassessing its trust in U.S. leadership and why the outcome of the war may depend as much on Washington as it does on Moscow.
A reframing of war: the Feb. 24 UN resolution
On Feb. 24, the U.S. voted with China and Russia on a UN Security Council resolution that referred to the Ukraine war as a conflict “between Russia and Ukraine,” omitting any reference to Russian aggression or demands for troop withdrawal. European allies abstained from the vote, a move that highlighted a rare transatlantic rift.
“The real break in U.S. foreign policy became public before the meeting in the Oval Office,” Peter Wallensteen, Richard G. Starmann Sr. research professor emeritus of peace studies wrote. “The new resolution only ‘implores a swift end to the conflict’ without any specification of measures, notably by Russia.”
According to Wallensteen, this rhetorical shift not only dilutes international condemnation of Russia, but also undermines past resolutions passed by the UN General Assembly that framed the war as one of unprovoked aggression. In practical terms, this change signaled to U.S. allies that Washington may be recalibrating its priorities away from full-throated support of Ukrainian sovereignty.
The Oval Office meeting and European fallout
Four days later, President Trump met with President Zelensky, dismissing Ukraine's negotiating leverage, telling Zelensky, “You don’t have any cards.”
George Lopez, Rev. Theodore M. Hesburgh, C.S.C., professor emeritus of peace studies, described the meeting as a “travesty” and said, “What really matters is the way the White House reinforced afterwards that we and the Russians are going to determine the peace.”
Lopez explained that the supposed ceasefire discussed by Trump and Putin unraveled almost immediately.
“The very first night the ceasefire was supposed to take effect, Putin made a mockery of the agreement. This isn't a ceasefire; it's a political smokescreen,” he said.
He shared that for European allies, the failure of the ceasefire and the exclusion of EU voices from peace discussions were red flags. “There’s no confidence. There’s no agreement with Trump’s position. They're not going to wait for the U.S. anymore,” Lopez added.
A shift toward strategic autonomy
Laurie Nathan, professor of the practice of mediation and director of the mediation program, described the fallout as a catalyst for change within the EU. “Europe won't ask Trump to join anymore. They'll find their own way,” he said.
French President Emmanuel Macron has long advocated for “strategic autonomy” within European security policy, and recent developments appear to have accelerated that vision. With U.S. reliability in question, the EU is advancing internal defense frameworks through initiatives such as the European Peace Facility and coordinated defense procurement programs.
“It’s already shifted the way Europe is going to go about its business,” Lopez said. “Trump foreign policy is punished first, then see where it goes. It’s coercive and reactionary.”
The cost of peace: a political and moral dilemma
When asked about potential peace terms, Nathan argued that Western observers often fail to understand Ukraine's perspective. To illustrate, he drew a sharp analogy: “Would the U.S., if it were attacked by Mexico and they seized Texas, just give up Texas to stop bloodshed? No one in Texas would agree. No one in America would agree,” he said.
Nathan stressed that Ukraine continues to weigh these impossible choices. “Zelensky and Ukraine are calculating the costs of continued fighting — bloodshed, destruction of infrastructure — against the political and moral cost of surrendering sovereign territory,” he said.
He added, “They're willing to endure a lot of pain rather than compromise their sovereignty. That tells you where they draw the line.”
Trump as a game-changer: unpredictability and disruption
Nathan emphasized the singular role of the United States in shaping the outcome of the war. “He’s a game changer. There’s no other country that is a game changer here. The EU, China — they matter, but none of them hold that kind of leverage,” he said.
He warned that Trump’s influence is made more dangerous by his unpredictability. “Trump isn’t value-based. He’s transactional. What serves his personal or commercial interests guides his decisions, not democratic values or stability,” he added.
Nathan also pointed out that Trump’s current stance is a departure from decades of U.S. foreign policy, saying, “He’s breaking not only from Biden’s position, but from the Republican Party’s historical stance, which opposed Russian aggression.”
The UN Security Council: power vs. principle
Nathan explained that the failures of the UN Security Council have been especially visible in the current conflict. He added that the Council is not a neutral global body, but a reflection of geopolitical power.
“It comprises five permanent members — the P5: the U.S., Russia, China, France and the UK. Each has veto power. It’s about power, not justice," Nathan said. “If Trump says the Council is ineffective, he’s partly right — and he’s part of the reason why.”
He continued, “When either the U.S. or Russia blocks resolutions for political reasons, the Council becomes paralyzed. It's not about fairness. It reflects global hierarchies born out of World War II.”
UN relations in decline
Lopez stated that the erosion of U.S. alignment with traditional allies has had broader consequences. “The United States has moved away from alignment with Britain and France and now seems to align more with Russia and China. That’s damaging to how the world sees us,” he said.
Nathan added that this shift is not merely diplomatic. “Trump is doing long-term damage to the U.S.-UN relationship and to our standing among democratic nations in the UN,” he said.
Beyond the battlefield: what peace would require
Wallensteen warned that surface-level diplomacy will not end the war. “Peace will require resolution of territorial disputes, security guarantees, withdrawal of troops, constitutional reforms, prisoner exchanges, and reparations. A ceasefire alone is not sufficient,” he said.
Lopez echoed this view, emphasizing that Ukraine cannot be expected to give up strategic assets or territories in exchange for short-term relief. “Trump’s style is erratic and coercive. No country would agree to hand over its economic resources, like rare minerals, to an unpredictable partner,” he shared.
Escalation in Kyiv, and a Trump reversal?
On April 24, a Russian missile barrage killed at least 12 and injured over 90 civilians in Kyiv — the deadliest strike on the capital in nearly a year. Hours earlier, President Trump had accused Zelensky of being the main impediment to peace.
Following the attack, Trump issued a rare public rebuke of Russian President Vladimir Putin. “Vladimir, STOP!” he wrote on his social media platform. “I am not happy with the Russian strikes on KYIV. Not necessary, and very bad timing.”
At a press briefing later that day, Trump claimed he was “putting a lot of pressure on Russia behind the scenes” and referenced a “pretty big concession,” which he defined as “stopping taking the whole country.”
Despite the rhetorical shift, Trump maintained that he has “no allegiance” to either side and reiterated his intention to “stop the fighting and save lives” — a position European diplomats said reflected an American proposal too favorable to Moscow.
“Most European leaders agree on the need for some sort of territorial compromise, but one foisted on themselves and the Ukrainians.” said Camille Grand, a former senior NATO official who leads defense studies at the European Council on Foreign Relations in a The New York Times article.
Is peace possible?
In conflict mediation, the idea of “ripeness” describes the moment when both sides believe that continued fighting no longer yields gains.
“You wouldn’t put Russia and Ukraine there,” Nathan said. “Neither side believes it’s time to negotiate. Both still think they can improve their position.”
Until that changes, and until a consistent, credible mediator emerges, the war is likely to persist — with global consequences far beyond the battlefield.
