There is another scenario, however, in which this dilemma diminishes because the stalemate breaks in Ukraine’s favor. This is the future that the Ukrainian military claims is within reach — where with sufficient military aid and hardware they are able to turn their modest counteroffensives into major ones and push the Russians back not just to prewar lines but potentially out of Ukrainian territory entirely.

Clearly, this is the future America should want — except for the extremely important caveat that it’s also the future where Russian nuclear escalation suddenly becomes much more likely than it is right now.

We know that Russian military doctrine envisions using tactical nuclear weapons defensively, to turn the tide in a losing war. We should assume that Putin and his circle regard total defeat in Ukraine as a regime-threatening scenario. Combine those realities with a world where the Russians are suddenly being routed, their territorial gains evaporating, and you have the most nuclear-shadowed military situation since our naval blockade of Cuba in 1962.