Look out: The libertarians are coming! The libertarians are coming! Never before have so many been so intimidated by so few, with so little political power.

Salon.com offers near-daily warnings about the libertarian “threat”:

• It's corrupting progressivism: “Don't ally with libertarians: Ideologues co-opt an anti-NSA rally.”

• It's even infecting your iPhone apps: “The Secret Libertarianism of Uber and Airbnb.”

“ Beware of Libertarians Bearing Gifts,” the Center for American Progress admonishes: “a bipartisan move against the NSA could kill the New Deal.”

Anti-libertarian paranoia plagues our elected officials too: “the anarchists have taken over,” Sen. Harry Reid, D-Nev., wails. “This strain of libertarianism ... is a very dangerous thought," New Jersey Governor Chris Christie warned last summer in the wake of Edward Snowden's exposure of National Security Agency spying: “I want [these critics] to come to New Jersey and sit across from the widows and the orphans” (Pro tip: don't take the George Washington Bridge).

“I’m very nervous about the direction this is moving in,” the governor added.

Recently, three prestigious academics have argued that you should be especially nervous about “Paranoid Libertarians.” Distinguished historian Sean Wilentz coined the term last month in a New Republic hit piece on Snowden and journalist Glenn Greenwald. These NSA critics “despise the liberal state and want to wound it,” he charged.

Picking up Wilentz's term, Harvard law professor and former Obama administration regulatory czar Cass Sunstein offered tips on “How to Spot a Paranoid Libertarian.” And, writing at Slate, the University of Chicago's Eric Posner warned that libertarian paranoia kills: “in fact, the fear of government is far more serious than the fear of flying.”

The three combined for nearly 10,000 words on “Paranoid Libertarians” without ever producing evidence that “libertarian paranoia” is a threat to much of anything besides overweening government.

Wilentz's article is a comically inept exercise in guilt by association. Liberals shouldn't make common cause with Snowden and Greenwald, says Wilentz, because, among other things, Snowden gave $500 to the Ron Paul campaign and made disparaging comments about Social Security in an Internet chat room in 2009. Greenwald has (gasp!) written for, and said nice things about, my employer, the Cato Institute.

Sunstein offers a more reasonable critique, distinguishing between “Paranoid Libertarians” and libertarians in general, who are “speaking on behalf of an important strand in America's political culture.” He's worried about the movement's fringe, he says, those who “have a wildly exaggerated sense of risks to liberty ... adopt a presumption of bad faith on the part of government ... [and] love slippery-slope arguments.”

Their overwrought attitude toward the risks of government abuse, Sunstein and Posner suggest, might lead them to resist sensible policies making Americans safer.

If, as Posner asserts, “fear of government is far more serious than fear of flying,” it must be serious indeed. Increased driving after Sept. 11, 2001, may have led to more than 1,500 additional road deaths in the year after the attacks. How many people did post- 9/11 fear of government kill?

Both professors are heavy on concerns and light on specifics. Sunstein points to a nine-year-old paper by his colleague Adrian Vermuele on the danger of “Libertarian Panics.” That paper offers two historical examples of the terrible consequences that can ensue when people let themselves get carried away by distrust of government. They are, and I'm not making this up: (1) the American Revolution; and (2) political resistance to the PATRIOT Act during the mid-2000s.

The American Revolution seems to have worked out ok, and given recent revelations, if anything, civil libertarians weren't paranoid enough about the PATRIOT Act circa 2005. If this is the best they can come up with, we needn't panic about “libertarian panics.”

GENE HEALY, a Washington Examiner columnist, is vice president at the Cato Institute and author of "The Cult of the Presidency."