WASHINGTON

Over the last few years, Republicans have been retreating from policy ground they once held and salting the earth after them. This has coincided with, and perhaps even been driven by, the Democratic Party pushing into policy positions they once rejected as overly conservative. • The result is that the range of policies you can hold and still be a Republican is much narrower than it was in, say, 2005. That's left a lot of once-Republican wonks without an obvious political home. • Health care is the most obvious example. The basic architecture of the Affordable Care Act is, as has been pointed out ad nauseam, a Republican idea. It was first proposed in a 1993 plan that had 20 Senate Republicans as co-sponsors. It was passed and implemented by then-Gov. Mitt Romney in Massachusetts. It was supported by Newt Gingrich. Through much of this time, Democrats viewed it with skepticism: They wanted something closer to single payer. But key Democrats dropped those objections in order to actually pass health reform.

Republicans could've pocketed the Democratic concession as a win. They could've celebrated the triumph of their ideas and the Democratic abandonment of single payer. They could've used the Affordable Care Act as a vehicle to push some of their other health policy initiatives, like medical malpractice reform, capping the employer tax exclusion and spreading health savings accounts.

Instead, they abandoned every idea even vaguely related to the Affordable Care Act. In fact, they pretty much abandoned all ideas related to universal coverage, or even big expansions of coverage. They decided some of them were downright unconstitutional. Today, House Majority Leader Eric Cantor , R-Va., can't even get high-risk pools past his members. The health policy space on the right is radically narrower than it was a decade ago.

Health care isn't the only example. There was a time when Republicans were leading the way on ideas to fight climate change. The first cap-and-trade bill to reduce carbon emissions was introduced into the Senate by John McCain, R-Ariz. The McCain-Palin ticket included a cap-and-trade plank.

There's no serious support in today's Republican Party for doing anything about climate change. Today's Republican Party doesn't want a cap-and-trade plan or a carbon tax or even money for renewable energy research. Whereas a decade ago a policy wonk who worried about the future of Earth could comfortably fit in the GOP, today anyone who wants to do anything serious about climate change has been written out of the party.

It doesn't end with health care and climate change. In 2008, President George W. Bush pushed for and signed the Economic Stimulus Act. In 2009, there were a variety of Republican stimulus plans. Back then, Republicans could believe in deficit-financed stimulus during an economic downturn. Today, that would get you driven out of the party as a Keynesian spy.

And the GOP's intense commitment to the antitax pledge is a real problem for policy wonks with even a passing understanding of what's driving deficits. In my experience, most Republican policy types will tell you, behind closed doors, that the anti-tax dogma is strategic and the Republican Party is just smartly negotiating for the most possible entitlement cuts. They know the taxes are needed eventually. This requires basically believing every elected official in the Republican Party is a liar.

As the Republican Party's range of acceptable policies has narrowed, the Democratic Party's range has expanded. Stimulus based entirely on tax cuts? It's not their preference, but they'll take it. Market-based approaches to environmental regulation? Sure, why not? Capping the employer-based exclusion for health care? Of course. Hundreds of billions of dollars in entitlement cuts to help reduce the deficit? Uh-huh.

Imagine a policy spectrum that goes from 1 to 10 in which 1 is the most liberal policy, 10 is the most conservative policy and 5 is that middle zone that used to hold moderate Democrats and Republicans. The basic shape of American politics today is that the Obama administration can and will get Democrats to agree to anything ranging from 1 to 7.5 and Republicans will reject anything that's not an 8, 9 or 10. The result, as I've written before, is that President Barack Obama's record makes him look like a moderate Republican from the late 1990s.

This, by the way, is why I'm down on the terms "liberal" and "conservative" or "left" and "right" in today's Washington. Too often the terms are used as shorthand for "person who mostly agrees with Democrats" and "person who mostly agrees with Republicans." If Gingrich or Romney in 2005 could be counted as a liberal today, something has gone wrong with the way we're labeling the political spectrum.

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