Russia had long viewed Crimea as part of its territory (the region was gifted in 1954 to Ukraine by former Soviet leader Nikita Khrushchev), and Ukraine as part of its sphere of influence. The pro-Western government in Kiev has angered Moscow, and at least some of its actions in the country can be attributed to Russia’s regional status.

Though the U.S. has maintained its opposition to Moscow’s cross-border activity, it has stopped short of providing lethal arms to Ukraine. Steven Pifer, a senior fellow at the Brookings Institution and a former U.S. ambassador to Ukraine during the Clinton administration, told me this policy was due in large part to President Obama’s opposition to providing lethal aid in fear of escalating the violence. “People were not two years ago going to say ‘We like the idea,’ because they knew it was a presidential decision and they knew the president was cautious,” Pifer said. “In this case, I don’t think President Trump has taken a position, so they may feel they have a little bit more leeway.”

Trump has offered little specificity on his stance over the Ukrainian conflict, but he hasn’t formally ruled out providing arms either. Trump called on Moscow to “cease its destabilizing activities in Ukraine and elsewhere” during his visit to Poland earlier this month, and told Ukrainian President Petro Poroshenko last month during his visit to Washington that the crisis is one “we’ve all been very much involved in.” But where Trump hasn’t been specific, others in the government have. In an address this month to the Senate Armed Services Committee, Air Force General Paul J. Selva, the vice chairman of the Joint Chiefs of Staff, said lethal defensive aid to Ukraine is “more than just a military recommendation,” adding: “This will be a policy choice on whether or not we’re going to give the Ukrainian government the tools they need to defend themselves against what we believe to be a Russian-supported insurgency movement in the Donbass,” referring to the region in eastern Ukraine.

More than just giving Ukrainian forces a means to defend themselves, Pifer said the arms could serve as a way to compel Moscow toward a political resolution to the conflict. “Nobody on the Ukrainian side suggests to us that they were going to use the force to drive the Russians and the separatists out of Donbass—they know they cannot beat the Red Army,” he said, referring to the Russian military. “The advantage ... is giving them better ability to raise the cost to the Russians and the separatists of further aggression.”

The Russians may not see it that way. Though Volker insisted that arming Ukrainian forces would not be seen as a provocation, Moscow is unlikely to look on the move as kindly either. “There is a risk the Russians choose to escalate, and I think it’s a risk we have to acknowledge,” Pifer said, noting that as long as the Russians are disinclined to resolve the conflict, it could remain at a standstill.

“It hasn’t yet reached the point where they’re looking for a way out,” he added. “We’ve got to somehow figure out a way to change the calculation in the Kremlin.”