“An article in The National Interest months ago asserted the US would be the chief obstacle to peace in Ukraine.”
The chief obstacle to peace in the Ukraine is Vladimir Putin. He can end the war any time he chooses.
True, Putin could have surrendered Russian sovereignty as the Capitol District oligarchs worked to put their boot on Russia's neck. Personally I prefer a multi-polar world, warts and all, to one dominated by the same monstrous cabal that has come to power over us.