The decision to go to war was Russia’s, and Russia bears ultimate responsibility for what happens now. But that does not absolve the West of its strategic incompetence and complacency, and it does not mean the United States and its allies are guiltless in all of this.
At multiple points leading up to the current crisis, there were ways for the United States and Europe to create off-ramps for both Moscow and Kyiv, to shepherd a negotiated settlement so that both sides got a minimum of what they needed, and some of what they wanted.
What might that have looked like? For Moscow, a recognition of its strategic claim on Crimea and the port of Sevastopol as the home of its Black Sea Fleet. For Kyiv, the promise of political independence and greater integration with Europe in exchange for territorial concessions.