The key thing to understanding the debate over health care policy in the United States is that it’s not really about health care policy, it’s about money.

This may sound weird on first read, but there’s actually not a lot of disagreement about the basic contours of health care policy. It seems like there is. But most of the policy debates are proxies for the underlying disagreements over whether and how much government should spend on health care.

The political challenge for Republicans has always been how to mask their ideological preference not to spend much (or any) on health care. To do that, they’ve mounted a sustained decades-long attack on any reform efforts as too costly, inefficient, unworkable, and a threat to liberty. At the same time, they’ve had to come up with a proposals of their own to make it sound like they actually have a workable health care policy: tax credits, health savings accounts, high risk pools, etc.

Those conservative policy proposals are not in and of themselves entirely bad ideas. In theory, they are trying to achieve the same ends as progressive health care policies. Again, to bang the drum: There’s not that much disagreement over what health care policy needs to accomplish. But conservatives tend to want to underfund their own policies, too, and that means in general that they can’t possibly accomplish what their progressive policy counterparts would in terms of coverage or care.

That hasn’t mattered as much politically because Republicans haven’t been in a position to do much about it, or been forced to do much about it. They either ignored health care reform when they were in power, or opposed Democratic reforms when out of power. What’s changed is that with Obamacare already in place and Republicans saddled with their years-old promise to rip it out root and branch, they have to deal with it … now.

The other thing that’s changed is that with Republican control of all of Washington, the debate now is entirely on the GOP side of the aisle. Democrats are extraneous. So reconciling how much money to spend on health care is a debate among Republicans, partly over ideological differences and partly over political expediency. It’s a very painful, contentious and difficult-to-reconcile debate to be having within one’s own party at the very same time that repealing Obamacare is the No. 1 priority of the new Congress and President.

Tierney Sneed does a great job explaining all the ends and outs of the halting GOP plans to replace Obamacare in her new piece today. The key quote comes from one of our go-to health policy experts, Larry Levitt, vice president at the Kaiser Family Foundation. It captures the entire dynamic:

The tension between conservatives who want to spend less and moderates who are willing to maintain federal spending on health care to keep people covered will become very clear, sooner rather than later. The previous repeal-and-delay approach kind of deferred the big fights over money, but this approach would bring those fights on almost immediately.

That is the real fight unfolding. It’s internecine, it’s not clear who will prevail, and ultimately, and deeply ironically, it’s not really a debate about health care policy. It’s a debate about money.