By Friday, he was in full attack mode. During morning Executive Time, he let loose with a classic Twitter barrage, slamming Democrats and urging the Senate Republican leader, Mitch McConnell, to go “nuclear” if necessary — that is, blow up the legislative filibuster to push through an agreement with a simple majority of votes. Disinclined to abandon his institutional prerogatives for even the most magnificent wall, Mr. McConnell immediately made clear this was not an option.

At an afternoon bill signing, the president continued trying to shift blame onto Democrats, calling the wall “an issue of crime” and “safety,” claiming that it would “pay for itself on a monthly basis” and asserting that even President Ronald Reagan had failed in his quest for a border wall (which, in fact, Mr. Reagan never sought).

Senators trickled back into town to vote on a procedural motion on whether to move forward with the House’s latest proposal, which includes Mr. Trump’s wall money. But Senate leaders made clear that nothing was likely to move until a new bipartisan compromise could be reached. Midafternoon, Ms. Sanders told Roll Call that there might be some lower level of wall funding that would satisfy the president. The talks to resolve the dispute collapsed Friday night. And the shutdown became a certainty.

This is what happens when the nation’s chief executive holds a leadership philosophy akin to that of the Petyr Baelish character on “Game of Thrones” — namely, that “chaos is a ladder.” For most people, uncertainty and disorder are scary, unsettling forces to be avoided. But for Mr. Trump, they are cherished friends and strategic assets, in part specifically because other people are so anxious to avoid them. The president clearly believes that throwing everyone else off balance gives him an edge — that is, if he can make the turmoil fierce enough, those around him will give up and give in.

Better still, even when he doesn’t get his way, piling on the pandemonium keeps people from focusing on any one piece of it. The normal human mind can cope with only so much drama before it gets overloaded. Mr. Trump grasps better than most that a single scandal is cause for public outrage, while a million scandals is a statistic.