I haven’t written anything about the entirely predictable demise of the post-Newtown gun control push, but this passage from Politico’s coverage of last week’s Senate vote seemed worth a comment:

In the end, however, moderates and conservatives in the upper chamber said they simply couldn’t deal with a flurry of progressive issues at once — from gay marriage to immigration to guns. The other three Democratic “no” votes — Max Baucus of Montana, Mark Pryor of Arkansas and Mark Begich of Alaska — were never really in play, sources familiar with the situation told POLITICO. One senator told a White House official that it was “Guns, gays and immigration – it’s too much. I can be with you on one or two of them, but not all three.”

The first paragraph’s conservative-versus-progressive frame is useful for understanding why this particular group of issues creates pressures on centrist, purple-state Democrats. But to understand why gun control in particular was the bridge too far, it’s worth reaching for a slightly more esoteric political category — namely, “liberaltarianism,” a phrase coined in 2006 by Brink Lindsey, then of the Cato Institute, to describe the possibility of a liberal-libertarian rapprochement.

Lindsey had an ambitious vision of what his proposed fusion would involve: Liberals and libertarians would embrace their pre-existing common ground on civil liberties (or what looked like common ground in the Cheney era) and most social issues, and then they would jointly “elaborate a vision of economic policy” that would promote libertarian ideas about free enterprise and a light regulatory footprint as a means to sustaining the liberal vision of a sturdy social safety net. “On the one hand,” he wrote, trying to sketch this vision out, “restrictions on competition and burdens on private initiative would be lifted … At the same time, some of the resulting wealth-creation would be used to improve safety-net policies that help those at the bottom.”

I think it’s fair to say that Obama-era liberalism hasn’t lived up to this conception. Obama isn’t the Marxist of conservative paranoia, but his economic vision is far more dirigiste than libertarian — which is a big reason why many of the economic libertarians who had soured on the Bush-era G.O.P. ended up returning to the Republican fold. (Though not Lindsey himself, I should note.) On national security, meanwhile, the Democratic Party is plainly much less libertarian — and the Republican Party, mostly thanks to Rand Paul, slightly more so — than it was when Lindsey was drawing up his form of fusionism.

But on most cultural issues, the Democratic Party clearly has grown steadily more, well, “liberaltarian” since Lindsey coined the term. Again, if you look at things on a right-left axis, as the Politico piece quoted above does, the resistance to even modest gun control measures among many swing-state Democrats seems like the exception to the Obama-era party’s leftward shifts on gay marriage, immigration (where the party’s Byron Dorgans are all but extinct), and recreational drugs. But if you look at things from a libertarian perspective instead, it’s all perfectly consistent — the freedoms of gun owners being of a piece with the freedoms of migrants and pot smokers and gay couples — and an indication that the Democrats are simply becoming more culturally libertarian across the board.

When you combine this trend with the Republican Party’s sharp libertarian turn on economics and modest libertarian turn on civil liberties, you could argue that libertarian ideology has never enjoyed more bipartisan influence than it does right now. And yet a thoroughoing synthesis, of the kind that Lindsey hoped for, between libertarianism’s economic and social ideas seems as unlikely as ever. Instead, the kind of “liberaltarianism” that’s increasingly ascendant is one that combines a highly individualistic view of our social and cultural fabric, and government’s role therein, with a statist understanding of government’s role in providing economic security — and security, period. As Scott Galupo shrewdly puts it, it’s big government as “a guarantor of personal liberation and self-actualization” — unless your form of self-actualization runs afoul of the national security state, in which case you can be tried in a star chamber and executed by drone.

This is where the Democratic Party has been moving, in fits and starts, for some time now, but the Obama era has thrown the combination — an imperial presidency, a corporatist economic policy, and then a libertarian turn on almost every social issue — into sharp relief. It isn’t the liberaltarianism that Brink Lindsey had in mind, but it’s the liberaltarianism we seem destined to live under for at least a little while to come.