Once again, Democrats threaded the needle. They pushed through health care legislation that was much more ambitious than the Washington establishment deemed prudent, while rejecting the more sweeping call for single-payer health insurance and abandoning the public option to secure enough votes.

Democrats paid a political price for their decision, as the passage of Obamacare generated a furious backlash that cost them their House majority in 2010. But they achieved a policy goal liberals had been pursuing since the New Deal.

Compare that to the way Republicans have behaved. When Republicans had full control over Washington during the Bush era, they used their power to stomp all over conservative principles and drastically expand government.

This month, with limited control of Washington, Republican congressional leaders allowed themselves to be dragged by activist groups into a doomed budget showdown.

If Republicans want to advance the conservative agenda, they should study the way that Democrats balanced their liberal goals with the realities of legislating.