It’s not likely, says Pablo Calderon Martinez, an associate professor of politics and international relations at Northeastern University.
Can Europe alone sustain Ukraine’s effort to withstand Russia’s aggression without U.S. support?
Not likely, says Pablo Calderon Martinez, an associate professor of politics and international relations at Northeastern University.
“I don’t see [how] Europe can continue fighting this war without explicit U.S. support,” he says. “The balance tilted much more in favor of Russia in this conflict.”
Ukraine received $138.7 billion from Europe in 2022-2024, compared to about $119.7 billion from the U.S., according to BBC and the Kiel Institute for the World Economy.
According to the U.S. Department of Defense, the U.S. appropriated $182.8 billion for Operation Atlantic Resolve — a response to Russia’s invasion of Ukraine — including U.S. military training in Europe and replenishment of U.S. defence stocks.
Replacing U.S. aid will take months, if not years, says Calderon Martinez, citing sluggish economic growth in France, the U.K., and Italy, along with Germany’s ongoing recession since 2023.
“You’re going to have to cut from somewhere else: hospitals, schools, teachers, nurses, police officers,” he says. “There’s still the cost of living crisis being felt across the continent.”
Calderon Martinez says Europe cannot quickly fill in the gap in aid to Ukraine or match the U.S. deterrence power.
Josephine Harmon, an assistant professor in political science at Northeastern, remains more optimistic, acknowledging that while Europe faces a major challenge in providing 100% of Ukraine’s aid, the stakes for European security are too high to ignore.
“We’re seeing the Europeans move incredibly fast on this issue, because it’s a necessity,” she says.
The U.S. withdrawal of aid has forced the EU to confront its lack of a unified defense infrastructure and policy. In response, European Commission President Ursula von der Leyen announced the ReArm Europe Plan on Tuesday, proposing an €800 billion increase in EU defense spending over four years.
“Europe is ready to massively boost its defense spending both to respond to the short-term urgency to act and to support Ukraine, but also to address the long-term need to take on much more responsibility for our own European security,” von der Leyen said.
There is strong public support for aiding Ukraine, Harmon says, as many recognize that Ukraine is bearing the brunt of defending Europe’s eastern flank.
“It’s in the interests of other nations to invest their defense resources in that region because, ultimately, it strengthens their own national security as well,” she says.
While short-term aid levels may fall short, Harmon believes European nations will remain committed to supporting Ukraine rather than pressing for an immediate peace settlement.
Preventing Russian aggression from spreading further into Eastern Europe is a top security priority for Europe, Harmon says, especially for countries like Moldova and the Baltic states — Estonia, Lithuania and Latvia.
Because the Baltics are EU and NATO members, any Russian incursion into their territory would likely trigger a broader regional conflict, she explains.
“The region wants peace and does not want an aggressive neighbor threatening its eastern border or the integrity and sovereignty of the European Union,” Harmon says.
European leaders see defense spending as both a security measure and an economic stimulus, boosting industrial activity and manufacturing, Harmon says.
To ease criticism of increased aid to Ukraine, U.K. Prime Minister Keir Starmer pledged to fund it through cuts to international aid rather than domestic programs.
“I think we’ll end up where we are now — continuing policy, increasing aid and sustaining the war effort,” Harmon says.
Europe could offer Ukraine EU membership as a security guarantee, but Russia would likely reject it due to the potential NATO accession, Calderon Martinez says.
“Having European peacekeepers on the Russia-Ukraine border could provide additional security. If Russia decides to attack again, then you’ll have to engage with European troops on the ground,” he says.
But it would be “completely extraordinary,” Calderon Martinez adds, if Russia and Europe manage to sign a peace agreement without U.S. involvement.