It’s certainly not Kirstjen Nielsen, who got the boot yesterday. It’s not Claire Grady, the former #3 at the Department of Homeland Security who would have ascended to acting Secretary otherwise, and who resigned under pressure to avoid that outcome. When asked if the exodus at the department was intended to leave adviser Stephen Miller in de facto control of immigration enforcement, Donald Trump told the media that they had it all wrong. Miller’s “a brilliant man,” Trump announced, but “there’s only one person running” Homeland Security.

And it’s not Kevin McAleenan, either:

President Donald Trump claimed Wednesday that it didn’t matter who ran the Department of Homeland Security because the true person in charge is ‘me.’

‘There’s only one person that’s running it. Do you know who that is? It’s me,’ Trump said in response to a question from DailyMail.com before he left the White House for a trip to Texas.

The president was also asked if he’d considering appointing his hardline adviser Stephen Miller to the job as Miller directs immigration policy in the White House and has been behind the push for Trump’s ‘tougher’ border stance. …

‘Steven is an excellent guy. He’s a wonderful person. People don’t know him. He has been with me from the beginning. He is a brilliant man,’ the president said.

The question that prompted Trump’s defense of Miller is silly on its face. There is no way that Trump would give the Senate a chance to question Miller in a confirmation hearing for any position, let alone the Cabinet position for Homeland Security. Besides, Miller works for Trump in developing policy; a Homeland Security Secretary assists in that process but is more tasked for carrying it out.

Trump’s point is valid in the sense that he’s ultimately responsible for the performance of Homeland Security. However, he’s not in charge in any meaningful operational way, and it’s not clear that anyone is at the moment. Thanks to the exodus over the last couple of days, the top three positions at Homeland Security are now empty (the #2 position had been vacant prior to this). Moving McAleenan up means leaving the top position at Customs and Border Patrol empty. Lee Francis Cissna at Customs and Immigration Services is apparently on the way out as director, and the appointment of Ronald Vitiello for the open director spot at Immigrations and Customs Enforcement has been rescinded.

Trump may deny that a purge has taken place, but that’s a lot of command posts left empty all at once. As I argue in my column at The Week, that will create months of chaos that will interfere with Trump’s ability to make good on his immigration-enforcement promises. But does Trump want chaos for strategic purposes?

Put simply, the exodus at homeland security is a recipe for chaos, and a gaping hole on the GOP’s political flank. Democratic presidential contenders will have easy targets in the new nominees when Trump gets around to appointing replacements. Senate Democrats will have multiple opportunities to rip homeland security policies and actions in the confirmation hearings. Those may not be as contentious as the Brett Kavanaugh hearings, but they won’t be collegial affairs, either.

Perhaps Trump wants chaos, however. Trump tried arguing that the nation had an emergency on the southern border in the midterms, only to have that message flop in suburban districts as Republicans lost the House. He stuck to that argument through a government shutdown and now into a legal fight over his National Emergencies Act declaration. By clearing out so many top officials at once in the homeland security department, Trump has exacerbated the emergency by adding administrative chaos — which he can argue was necessary in order to get officials in Washington to take it seriously.

That sets up a stark contrast with Democrats who insist there isn’t any emergency at all, nor any need to build a wall to mitigate it. That worked in the midterms when the scope of the migrant rush to the border wasn’t as clear as it is now. Will it work again with Trump at the top of the ticket? Democrats dismissed his immigration alarmism in 2016 and ended up getting burned. If they don’t move at all in Trump’s direction between now and November 2020, they might score big again as they did last year — or get caught with their pants down as they did in 2016.

Will Republicans in Congress unite behind Trump in this new strategy of top-down chaos? Grassley’s reaction might be a warning sign, but Mitt Romney sent a surprising signal of solidarity with Trump on Sunday. The Utah senator and frequent Trump critic told NBC’s Chuck Todd on Meet the Press that “the president has tapped into something which the people feel very deeply” on border security. “This is a winning issue, I think, for Republicans,” Romney said, “but more importantly a winning issue for Americans to say, ‘We have to have sovereignty of our nation.”

That’s a hell of a gamble. Trump must hope that Democratic obstruction to his nominees will shift the blame for the chaos, but Republicans can confirm anyone on a strict party vote. In the meantime, the organizational confusion will make an emergency situation even more acute, leaving Trump with even less direct methods of dealing with it. It’s tough to see a positive end game here.