Even so, attempts to bring the three nations into the European Union had stalled in the years prior to Russia’s full-scale invasion of Ukraine.

The beginning of that war “really created this sense of urgency and also really led the E.U. to extend the membership prospect to these three new countries in the East: Ukraine, Georgia and Moldova,” said Marta Mucznik, a senior E.U. analyst at international peace-advocacy nonprofit Crisis Group. 

Since then, the E.U. has moved to accelerate…