A failure by the United States to continue military aid to Ukraine would spell disaster for Ukraine and its Western allies while emboldening Russia and other potential aggressors.

When the Soviet Union collapsed more than thirty years ago, American leaders hoped that Russia would embark on a transition to free-market democracy. Shared democratic values, the thinking went, woul…

If Western allies fail to send Ukraine the weapons it needs, the odds increase of the war dragging on indefinitely, at a terrible cost to both Ukraine and Russia and a growing risk to the wider world…