Shutting down the government is usually the last thing the people in charge of government want to see, especially when it's your party in control of government, and especially when your party could be blamed for it a few weeks before voters pick a new Congress.
So why does Trump seem as if he wants a shutdown this autumn? A few theories, based on past shutdown fights in his presidency:
He thinks it's good politics: In his latest tweet, fired off Tuesday afternoon, Trump claims he doesn't care what the political ramifications of a shutdown are, but it's possible that politics is very much on his mind when he threatens these shutdowns.
Trump got elected on a message of sticking it to Washington — and judging by his campaign rhetoric, he's aware that sometimes includes Congress, even if his party controls Congress right now.
“I want the entire corrupt Washington establishment to hear the words from all of us,” he told supporters on election eve. “When we win tomorrow we are going to Washington, D.C., to drain the swamp.”
Since then, Trump has shown little to no concern about what Republicans in Congress want. He has taken a torpedo to Republican orthodoxy, forcing the party to bend on many issues, including its get-tough-approach on Russia and tariffs that Republicans loathe.
So it's not much of a surprise that Trump would shrug at what most Republican lawmakers shudder at, the idea of a shutdown. Last fall, The Washington Post's White House team reported that Trump told confidants a shutdown could be good for him, a way to flex his hard-line immigration muscles. Plus, he has tweeted stuff like this:
The start of 2018 brought another shutdown possibility for which Trump seemed downright eager: “I’d love to see a shutdown if we can’t get this stuff taken care of,” he said in February.
He really, really, really wants money for his wall along the U.S.-Mexico border: Trump could be calculating — perhaps correctly — that this fall's spending battle could be one of his last chances to secure tens of billions from Congress toward his key campaign promise before he's up for reelection in 2020.
A few weeks after the Sept. 30 spending deadline, it's possible and maybe even likely that Democrats will take back control of the House in November's midterm elections.
If that happens, it's possible and even likely that Democrats will block efforts by Trump to overhaul the immigration system or to fund his wall to any significant degree. (Though Senate Democratic leaders have previously offered the full $25 billion Trump wants in exchange for protection for "dreamers.") That would leave Trump stuck through 2020.
For Trump, it might come down to this binary choice: launch into a shutdown fight to try to get your wall; or back off for the sake of helping Republicans keep their majorities in Congress. Trump has given no reason to think he'll choose the latter.
He doesn't really want a shutdown. He just really likes talking about it. Trump has said that his hard-line immigration policies are a reason he got elected. So it's not a coincidence that he keeps tying a shutdown threat to those policies. Even if he doesn't go through with it — if past is precedent, he won't, since he has twice backed down from shutdown threats — talking tough could benefit him.
Sticking it to Washington politicians, playing by unconventional rules and touting his border wall. Those are all buzzy issues for his base, and Trump probably knows it. At the very least, talking about these issues can help distract from a rough few weeks after coming across as deferential to Russian President Vladimir Putin. Trump picked a lot of base-pleasing fights over the weekend: Russia; the media; a shutdown fight over the wall.
Trump is a wild card in these fights; he always has been. But this time, he seems to be showing his cards much earlier. It's possible he genuinely wants the government to shut down.