Liberals are furious, but the gun issue will not significantly damage the Republican Party. Sure, it looks bad to oppose background checks, which have overwhelming popular support. Sure, the Republican position will further taint the party's image in places like the suburbs of Philadelphia and northern Virginia. Sure, the party looks extreme when it can't accept a bill sponsored by the conservative Sen. Joe Manchin and the very conservative Sen. Pat Toomey.
But, let's face it, the gun issue has its own unique dynamic, which is that the people who oppose gun limits vote on this issue while the people who support them do not.
Moreover, Democrats never made a compelling case that the bill would have been effective, that it would have directly prevented future Sandy Hooks or lowered the murder rate nationwide. Even many of the bill's supporters were lukewarm about its contents.
The main reason the gun issue won't significantly harm Republicans is that it doesn't play into the core debate that will shape the future of the party. The issue that does that is immigration. The near-term future of American politics will be determined by who wins the immigration debate.
In the months since the election, a rift has opened between the Republicans you might call first-wave revolutionaries and those you might call second-wave revolutionaries. The first-wave revolutionaries (the party's congressional leaders) think of themselves as very conservative. They ejected the remaining moderates from their ranks. They sympathize with the tea party. They are loyal to Fox News and support a radical restructuring of the government.
These first-wave revolutionaries haven't softened their conservatism, but they are trying to adjust it to win majority support. They are trying to find policies to boost social mobility, so Republicans look less like the party of the rich. They are swinging behind immigration reform, believing that Hispanics won't even listen to Republicans until they put that issue in the rearview mirror.
The second-wave revolutionaries — like Rand Paul (on some issues), Jim DeMint, Ted Cruz and some of the cutting-edge talk radio jocks — see the first-wave revolutionaries as a bunch of incompetent establishmentarians. They speak of the Bush-Cheney administration as if it were some sort of liberal Republican regime run by Nelson Rockefeller and Jacob Javits. They argue that Republicans have lost elections recently because the party has been led by big-spending, mushy moderates like John McCain and Mitt Romney and managed by out-of-touch elitists like Karl Rove and Reince Priebus.
The second wavers are much more tactically aggressive, favoring filibusters and such when possible. What the party needs now, they argue, is an ultra-Goldwaterite insurgency that topples the "establishment," ditches immigration reform and wins Hispanic votes by appealing to the evangelicals among them and offering them economic liberty.
The first and second wavers are just beginning their immigration clash. A few weeks ago, I would have thought the pro-immigration forces had gigantic advantages, but now it is hard to be sure.
The immigration fight will be pitting a cohesive insurgent opposition force against a fragile coalition of bipartisan proponents who have to ambivalently defend a sprawling piece of compromise legislation. We've seen this kind of fight before. Things usually don't end up well for the proponents.