[Jonathan Chait] Of the various expressions of right-wing hysteria that have flowered over the past three years—goldbuggery, birtherism, death panels at home and imaginary apology tours by President Obama abroad—perhaps the strain that has taken deepest root within mainstream Republican circles is the terror that the achievements of the Obama administration may be irreversible, and that the time remaining to stop permanent nightfall is dwindling away.

“America is approaching a ‘tipping point’ beyond which the Nation will be unable to change course,” announces the dark, old-timey preamble to Paul Ryan’s “The Roadmap Plan,” a statement of fiscal principles that shaped the budget outline approved last spring by 98 percent of the House Republican caucus. Rick Santorum warns his audiences, “We are reaching a tipping point, folks, when those who pay are the minority and those who receive are the majority.” Even such a sober figure as Mitt Romney regularly says things like “We are only inches away from no longer being a free economy,” and that this election “could be our last chance.”

The Republican Party is in the grips of many fever dreams. But this is not one of them. To be sure, the apocalyptic ideological analysis—that “freedom” is incompatible with Clinton-era tax rates and Massachusetts-style health care—is pure crazy. But the panicked strategic analysis, and the sense of urgency it gives rise to, is actually quite sound. The modern GOP—the party of Nixon, Reagan, and both Bushes—is staring down its own demographic extinction. Right-wing warnings of impending tyranny express, in hyperbolic form, well-grounded dread: that conservative America will soon come to be dominated, in a semi-permanent fashion, by an ascendant Democratic coalition hostile to its outlook and interests. And this impending doom has colored the party’s frantic, fearful response to the Obama presidency.

The GOP has reason to be scared. Obama’s election was the vindication of a prediction made several years before by journalist John Judis and political scientist Ruy Teixeira in their 2002 book, The Emerging Democratic Majority. Despite the fact that George W. Bush then occupied the White House, Judis and Teixeira argued that demographic and political trends were converging in such a way as to form a ­natural-majority coalition for Democrats.