President Donald Trump is taking an unusual risk for a president: He’s setting himself up as the central player in a possible government shutdown.

“If we have to close down our government, we’re building that wall,” he said Tuesday in Arizona, referring to the physical barrier he promised to construct between the U.S. and Mexico.

Trump’s tactics don’t line up with the conventional presidential strategy of avoiding government shutdowns — or at least sidestepping blame.

It should be hard for him to point a finger at  Republicans in Congress when he is openly threatening to cause a shutdown. It will be even harder for him or his increasingly gun-shy allies on Capitol Hill to blame Democrats, because Republicans control both chambers of Congress and the White House. And it will be much easier for Congress to pass a spending bill without the money than with it.

That is, the old rules say he’s setting himself up to take it on the chin, both legislatively and in terms of becoming a lightning rod for voters who suddenly can’t get the services that their tax dollars pay for.

So, what is Trump up to?

I think he wants to take credit for the wall and a shutdown — at least he’s positioning himself that way.

It’s hard to think of convictions more core to the rise of the Tea Party than opposition to illegal immigration and a reinterpretation of small-government conservatism into no-government conservatism. By courting a shutdown, Trump can be a champion of both principles.

He wouldn’t be the first Republican official to conclude that taking responsibility for a government shutdown is more a matter of getting credit than shouldering blame. Ask Sen. Ted Cruz. The Texas Republican forced a shutdown in late 2013 despite the plaintive cries of fellow Republicans who were (mistakenly) certain the debacle would doom them to defeat in 2014 and possibly 2016.

Rather than becoming the goat who ate the Republican Party, Cruz solidified his position as a hero to many grassroots GOP voters. Though he didn’t win the Republican nomination in 2016, he proved the most resilient of Trump’s competitors.

If Trump were unwilling to shut down the government to get the wall, he’d be demonstrating to his voters that he doesn’t have the grit or determination to go all the way for their shared top legislative priority. He would be showing weakness; and that is neither Trump’s strength nor a way to please his base.

His premise, for now, seems to be that a government shutdown would cause so much political pain for lawmakers that they would ultimately choose to pass a spending bill with money for the wall rather than continue to suffer the wrath of constituents bereft of government services.

But one essential truth remains: most Americans don’t want the wall. It’s hard to see how halting government operations will force Congress to fund it.

Rather than Congress acceding to Trump’s wall dream, maybe he needs to cause his own voters enough pain through a shutdown that they ultimately decide it’s OK for him to give in.

That would hold everyone else in the country hostage for a while — maybe a long while — but it would prevent Trump from disappointing his base by funding every government function other than the very the symbol of their anti-illegal-immigrant fervor.

So, Trump has backed himself into a political corner, but it’s the one that is familiar and comfortable to him. He is standing with his base. Maybe he will back down in the end, but it seems that is his option of last resort.

The most consistent element of Trump’s political profile is his allegiance to his base — often at the expense, many fellow Republicans believe, of the rest of the party. And if there’s one thing that base loves more than the wall, it’s the prospect of disrupting the government.

A shutdown may not serve the best interests of Republicans in swing districts and states in the mid-term election or of the party’s hopes of keeping the White House in 2020, but it would feed the id of his movement. Don’t expect him to back down in the face of a shutdown. It seems pretty clear that he’s setting himself up to take credit for one.

Republican leaders who think that will hurt the party should be figuring out how to line up veto-proof two-thirds majorities to keep the government running. If they don’t, it could be a very long autumn in Washington — and a very long fall for the GOP — before Trump feels like he’s losing.