US President Donald Trump’s announcement that Ukraine will receive Patriot missile systems as part of a new package of US weaponry has been warmly welcomed in Kyiv as it reels under nightly Russian bombardments.

Sending U.S. Patriots marks a shift for Trump, who had previously refrained from approving new weapons shipments to Ukraine since he returned to the White House. It also comes as U.S. Senator Lindsey Graham announced record levels of U.S. arms would go to Ukraine, dealing a blow to Putin.

As the conflict in Ukraine labors into its third year, one question now lingers over the war: Can a rapid influx of Western arms and a threatening tariff threat pressure a change in Moscow’s calculus?