All along we've been told this was about aggressive expansionism and applied a strategy of deterrence. That was wrong.With the imposition of new U.S. sanctions on Russian oil producers and Treasury Secretary Scott Bessent’s dismissal of visiting Russian envoy Kirill Dmitriev as a “propagandist,” the Trump administration’s efforts to end the war in Ukraine seem to be hanging by a thread. Their success or failure will depend on a simple premise: one must understand a problem in order to resolve it. Unfortunately, the West has been misdiagnosing the problem it faces in Ukraine for more than a decade, with increasingly...