The unanswered question is: What becomes of the broken-hearted? Will they forgive Trump’s reversal on Afghanistan—a change of mind he actually acknowledged, for what may be the first time ever—if he doubles down on his “nationalist” views of trade and immigration? Will they see him as yet another president captured by the conventional Washington wisdom, which can never seem to figure out a way of disentangling the nation from a foreign conflict? Will they subject his future decisions to a more skeptical inquiry? Will his decision further erode his standing among those who tell pollsters they “strongly approve” of his presidency?

Those who saw in Trump a figure who might actually break with the bipartisan consensus of the last half-century-plus had every reason for their optimism. His background, his ego, his very disconnection from any taint of insiderism gave them reason to think that he would actually do what he had said he would do. We don’t know how large this group is, but it contains some of the most fervent and committed Trump supporters. What they now do with their shattered hopes is going to make a very big difference in the coming political wars.