There has been a lot of uncertainty about how Republicans are going to follow through on their long-held goal of repealing the Affordable Care Act, and in a press conference today, Senate Majority Leader Mitch McConnell offered a little more clarity — with some frightening implications for Americans’ health care.

The press conference was a little bit confusing because McConnell kept using the term “replacement” when it was pretty plain that what he actually meant was “repeal”; for instance, he said, “We’ll move first with the Obamacare replacement resolution and then we will come with what the replacement actually will be.” But after saying that a few times, the message got across: Repealing and replacing are going to be separate, and repeal will happen immediately in January. In other words, the Republican Congress is going to toss millions of Americans off a cliff, then shout down to them, “Don’t worry, we’ll get you some kind of parachute before you hit the ground! Probably!”

Why are they doing it this way? The best explanation is that after voting to repeal the law 60 times, the pressure from their base to immediately thrust a dagger into Obamacare’s heart is just too great. As Rep. Mark Walker said: “Literally every Republican member has made this part of their platform in running for Congress.” They know well the wrath of the conservative base, and they don’t want to incur it. Nothing would show their spinelessness more than failing to repeal the hated Obamacare when they have both houses of Congress and the White House in their possession.

Yet almost seven years after the law was passed, they still can’t agree on a replacement, and there’s also a growing realization that repeal is going to cause an absolute hurricane of disruption across the American health care system. I want to focus on three big groups of Americans, to demonstrate the fire Republicans are playing with when they talk about repealing the ACA:

New Medicaid recipients. Before the ACA, each state determined who was eligible for Medicaid, and in some states (particularly those controlled by Republicans), the requirements were shockingly stingy. The law expanded Medicaid, allowing everyone earning up to 138 percent of the poverty level ($27,821 for a family of three) to join the program. But 19 Republican-controlled states refused to accept the expansion, leaving millions with no insurance when the federal government was basically begging to insure them. Nevertheless, Medicaid still expanded dramatically as a result of the law. According to Charles Gaba, who meticulously tracks the progress of the ACA, 12.3 million more Americans now have Medicaid because of the law.

Those getting subsidies on the exchanges. In its attempt to make coverage affordable for everyone, the ACA established insurance exchanges with subsidies so that those who aren’t getting coverage through their employers and aren’t poor enough for Medicaid could buy insurance. Repealing the law snatches these subsidies away. Gaba estimates that nine million Americans get significant subsidies on the exchanges, and would therefore be unable to buy insurance once they’re taken away.

Those with pre-existing conditions. Most of this group wouldn’t lose their insurance right away if the ACA were repealed, but they would lose the security they now enjoy. If you repeal the entire law (which would require overcoming a filibuster), the provision forbidding insurance companies from denying people coverage because they have pre-existing conditions would be gone. Both Donald Trump and congressional Republicans have said that when they come up with a replacement for the ACA, they want to retain that provision. The problem is that if you keep the pre-existing condition ban but eliminate the law’s individual mandate, then people could just wait until they got sick and then apply for coverage, which would lead very quickly to the collapse of the entire private insurance market in America.

So Republicans are discussing a series of provisions to cover these people. One idea is a rule saying insurance companies have to cover you only if you maintain continuous coverage (i.e. not dropping your insurance and then seeking it again when you get sick — or because you lost your job and couldn’t afford it), coupled with “high-risk pools,” which are absolutely the worst way to cover those with serious conditions, because they put all the expensive patients together into one pool, which is the very opposite of how insurance is supposed to work.

The bottom line is that even in the best-case scenario after Republicans are through repealing and replacing, Americans with pre-existing conditions would be thrust into a much more complicated and uncertain situation than they enjoy right now, without the ACA’s guarantee that they can get the same coverage as anyone else without having to jump through a bunch of hoops or pay exorbitant premiums. And how many Americans is that? According to the Kaiser Family Foundation:

We estimate that 27% of adult Americans under the age of 65 have health conditions that would likely leave them uninsurable if they applied for individual market coverage under pre-ACA underwriting practices that existed in nearly all states.

That adds up to over 52 million people. Many of them have employer coverage, so they’re fine — for now. But repealing the ACA takes away their security for the future. It also would mean bringing back the insurance industry practices the law banned, like yearly and lifetime limits on coverage, and “recissions,” in which the insurance company boots you off your policy when you get sick or have an accident.

So to sum up, here are the immediate victims of Obamacare repeal:

  • 12 million Americans now on Medicaid lose coverage.
  • 9 million Americans now getting significant subsidies lose coverage.
  • 52 million Americans with pre-existing conditions lose security for the future.

That’s only part of the story; if Republicans follow through on their “repeal and delay” plan, the individual insurance market could collapse as insurers flee, leaving millions more without coverage. But to say there will be disruption, and an ensuing backlash, is a wee bit of an understatement.

That’s what Republicans are wrestling with right now. The problem is that their vision for health insurance in America is one that is as privatized as possible, with as few people as they can manage on government plans or getting government help. We had a version of that before the ACA, and the results were clear: if you had a stable employer or you had a lot of money, you could afford good coverage, but if you didn’t, you were probably in trouble. The market’s magic didn’t keep costs and premiums down; in fact, both were rising at a faster rate than they are now that the ACA has reined them in. But on a fundamental ideological level, Republicans have no problem with an insurance system that produces some winners and millions of losers.

Republicans will always be caught between their anti-government ideology and the public’s demand for secure health care, and once they come up with their “replacement” plan for Obamacare, they’ll either tell all those millions of people they’re on their own, or they’ll swallow more government involvement than they’d like in order to minimize the political damage. Either way, there’s still going to be a huge amount of human cost; the only question is whether it will be merely terrible or positively cataclysmic. At this point, even Republicans don’t know which path they’re going to choose.