Europe has fallen into recession again. Its leaders should be nervous.

This movement would be a boon for Europe’s populists. Countries are already seeing support for left- and right-wing populist parties holding steady or rising. Those parties would be the natural beneficiaries of anger toward the unending crisis. In Ireland, that could mean the party once tied to the terrorist Irish Republican Army, Sinn Fein, would likely form the next government. In Italy, such support would probably flow to a party descended from fascists, the Brothers of Italy, which is the only major party outside the technocratic government running the country. Belgium, one of the hardest-hit nations and home to the E.U. administrative capital of Brussels, is already seeing a rise in support for the far-right Vlaams Belang and the outwardly Marxist Workers’ Party. Imagine if the seat of the European Union is governed by anti-E.U. parties.