Trump now faces a mushrooming political crisis over his administration’s policy of separating children of unauthorized immigrants from their parents at the border. While Trump has often been confounded by the checks and balances of the courts and the Congress, this is a rare case where Trump alone really can fix it. With a single word, he could reverse the policy, which his administration implemented last month. Instead, however, Trump has spent days railing at Democrats and claiming that they are to blame. Late Monday afternoon, Homeland Security Secretary Kirstjen Nielsen stood in the White House briefing room and echoed Trump’s comments in Cleveland—but flipped 180 degrees.

“Congress and the courts created these problems, and Congress alone can fix it,” she said.

The administration’s aim seems to be to fire up Trump’s base with a hardline immigration policy he knows they want, while trying to bludgeon Democrats politically by blaming them for a policy that is broadly unpopular.

On Monday, he tweeted:

CHANGE THE LAWS! — Donald J. Trump (@realDonaldTrump) June 18, 2018

He added:

It is the Democrats fault for being weak and ineffective with Boarder Security and Crime. Tell them to start thinking about the people devastated by Crime coming from illegal immigration. Change the laws! — Donald J. Trump (@realDonaldTrump) June 18, 2018

Later on Monday, during an event to announce the creation of a space force, Trump once again repeated his lie that the separations are Democrats’ fault. “I’ll say it very honestly and I’ll say it straight,” he began, and then followed with a claim that was neither honest nor straight:

Immigration is the fault—and all of the problems that we’re having, because we cannot get them to sign legislation, we cannot get them even to the negotiating table—and I say it’s very strongly the Democrats’ fault. They’re really obstructionist and they are obstructing.

This is not true. In fact, as my colleagues and I have reported repeatedly, the policy dates to May, when Attorney General Jeff Sessions announced that the federal government would prosecute everyone caught crossing the border illegally. Because an existing legal settlement bars children from being imprisoned, that decision means children and parents are separated. The Trump administration knew this would happen from the start. In May, White House Chief of Staff John Kelly described separations as “a tough deterrent” to those who might try to cross. Sessions said around the same time, “If you don’t want your child separated, then don’t bring them across the border illegally.”

These statements, as well as plenty more from the administration, make clear how the policy came into place. The White House and the Justice Department made a calculated decision knowing what would happen, and deciding it was worth the risk.