My friends, we need to talk about "skinny repeal."

While it sounds less harmful than the other versions of health-care "reform" Republicans are toying with to repeal the Affordable Care Act, it's actually an extraordinarily dangerous idea, not least because Republicans may use it to do a whole lot of terrible things. And as I write, it looks like the thing most likely to pass the Senate. So let's break it down.

What the heck is skinny repeal? The idea is that instead of doing all the things Republicans want to do to Americans' health care, especially eviscerating Medicaid, this version of repeal would just do a few things. It would eliminate the individual and employer mandates, meaning people would no longer be required to carry insurance and employers would no longer have to provide it to their workers. And it would eliminate one particular tax that the ACA imposed, on medical devices.

On the face of it, that sounds less awful than it might be. Which is true, in the sense that it's less awful if I take an axe and chop off one of your arms than it would be if I then proceeded to chop off your other arm as well.

Because they're such spoilsports, Democrats asked the Congressional Budget Office to determine how many people would lose their insurance coverage under skinny repeal, and the CBO concluded that the figure would be 16 million — and it would cause an immediate 20 percent spike in premiums. Given that the other bills Republicans were considering would uninsure anywhere from 22 million to 32 million people, 16 million is a slight improvement.

But it's still 16 million people, which is quite a few. A great deal of the damage would come from the fact that skinny repeal would essentially destroy the individual insurance market. To understand why, you have to grasp what the individual and employer mandates were supposed to do in the first place. It was in part about simply making sure everyone is insured, but it was also about creating a viable market that would do what we wanted it to.

You see, the mandates were never ends in themselves, and they weren't driven by some dark statist impulse to have government dictate ordinary people's lives. They were a tool to solve a very specific problem. If you want to allow people to get insurance regardless of their pre-existing conditions — which nearly everyone at least claims they want — then you have to broaden the risk pool. You have to get everyone in the system — especially young, healthy people who often don't need insurance as much as older, sicker people — to spread costs as widely as possible. Requiring everyone to get insurance is a way to do that.

So if you take away the mandates, but still require insurers to cover everyone, regardless of their pre-existing conditions, then anyone would be free to not carry insurance and then just wait until they get sick or get in an accident to buy it. That would mean insurers would only be covering sick people, and they'd have to charge astronomical premiums. Or they'd just pull out of the market altogether.

That's what Republicans are voting for if they support skinny repeal, and some of them would apparently be fine with it. Sen. Rand Paul (R-Ky.) told The Washington Post's David Weigel, "The insurance market's a disaster now. No matter what you do, unless you're willing to repeal all the regulations, it'll be a disaster in 2018. It's not the fault of Republicans. It's the fault of ObamaCare." That burn-it-all-down attitude is disturbingly common among Republicans, including the president, who keeps saying how clever he thinks it would be to "let ObamaCare fail" even as his administration is actively trying to create a death spiral in the individual market.

But wait, some of them say — we don't really want skinny repeal to become law, we just want to use it as a vehicle to get to a conference committee, where we can then negotiate a compromise between what the House and Senate passed — in other words, an entirely new bill that will be what we really want. But is that going to happen? There's a genuine possibility that the House could look at what the Senate just went through, and say to themselves, "There's no way we'll ever get a compromise everybody can live with. We'll just pass the same skinny repeal the Senate passed, say 'We repealed ObamaCare!' and move on." Then it would become law, and we'd be forced to live with it.

Meanwhile, the idea that while it's less than optimal skinny repeal is better than nothing is common in the GOP. If it passes the Senate, the House will be faced with the choice of a bird in the hand or two in the bush: Just pass skinny repeal now and take the "win," or hope that a conference committee 1) comes up with a compromise, which can then 2) pass the Senate and 3) pass the House. You could easily see how they could be skeptical that all three of those eventualities will come to pass, and choose not to take the risk. That's despite the fact that some Republican senators are saying they're only supporting skinny repeal to get to a conference. "The substance of this is not relevant," said Sen. Bob Corker (R-Tenn.). "What's relevant is getting to conference."

Count me less than reassured.

The worst possible outcome is certainly that skinny repeal passes, the bills go to conference, and what comes out and passes both houses is something like the monstrosities they've been considering up until now, with huge cuts to Medicaid and the help people currently get to afford insurance, along with provisions that guarantee higher premiums and deductibles. But skinny repeal on its own is bad enough — and it just might be skinny enough to squeeze through.