Donald Trump has turned Obamacare repeal into a hostage situation.

With repeal and replace stalled, President Trump is now doing everything he can to destabilize health care markets in a desperate attempt to force Democrats to come to the negotiating table. After dramatically cutting advertising and outreach, the Trump administration announced on Thursday evening that it would end cost-sharing reduction subsidies that help millions of lower-income Americans afford health insurance. According to the Congressional Budget Office, the move will increase premiums by 20 percent by 2018 and 25 percent in 2020 while adding billions to the deficit.

On Friday morning, Trump made it clear that these moves were being made for entirely political reasons:

Congress failed to repeal and replace Obamacare in part because it would create this exact situation: costs will go up and coverage will decrease. These moves to gut Obamacare do nothing to make health care more affordable, as Trump repeatedly promised he would do during the 2016 campaign, and instead aim to create a situation in which millions lose their health care, prompting Democrats to act.

Trump is, in effect, creating a hostage situation, something he’s repeatedly threatened to do in the past. But it’s highly likely this gambit will backfire. These moves—coupled with the administration’s troubling demands regarding a legislative solution for Dreamers—substantially increase the likelihood of a government shutdown. Trump has said he welcomes a shutdown in the past, so that may very well be the goal here. But that would be a substantial miscalculation. The Republican Party controls Congress and the White House and, if such a shutdown were to occur it would occur because of moves that Trump made. Republicans would be blamed.

And yet this miscalculation—that taking Obamacare hostage will somehow create the conditions for a political “win”—is at the root of these moves. If Republicans in Congress are smart, they’ll figure this out and do something to stabilize markets and protect Dreamers—but that’s never a safe bet. Instead, this seems like a miscalculation that will have substantial and devastating consequences for millions.