Who will pay for Ukraine’s war effort now the Trump administration has turned off the financial taps? European leaders have expressed themselves ready and willing to take up the burden, with European Commission President Ursula von der Leyen affirming that “if we continue to believe that Ukraine is our first line of defense, we need to step up our assistance.”

Individual countries have come up with generous funding packages – most open-handed of all being Germany, which has recently pledged more than €3 billion in direct funding. But that’s just a drop in the ocean compared…