Anybody who thinks the Obama years have been uniquely dominated by Teh Crazy should give a few minutes attention to the career of Michael Scheuer, once one of the most prominent critics of the Bush administration’s war on terror.

Scheuer’s career reached its terminal nadir last week, when he published a column endorsing an assassination of President Obama and Prime Minister David Cameron. In the modern media environment, it’s pretty hard to go too far. Advocacy of murder, however, does cross one of the last remaining lines. These words from the same column cross another:

“That Eric Holder and Barack Obama have not been impeached, moreover, suggests that the impeachment provisions of the Constitution are a dead letter; that they apply only to individuals named Nixon; or that they do not apply to black Americans supported by such towering giants of fatuousness as Oprah, Chris Matthews, Fareed Zakaria, Piers Morgan, and Hillary Clinton and her motley band of Viragos.”

I don’t expect we will be hearing much more in future from the former CBS News analyst, bestselling author, and CIA officer.

Yet Scheuer was not significantly less nuts during his hour of celebrity than he is today. In the pages of the book that made him famous, he revealed himself as a paranoid character, strongly tinged with anti-Semitism. Back in 2004, however, none of that mattered. Here was a figure with plausible national-security credentials (he’d worked at the CIA’s bin Laden desk!) who argued that the Iraq War was a debacle, that the Afghanistan War was a mistake. Just as any stick will do to beat a dog, so any criticism would do against Bush.

Those were the days when the U.S. was criticized both for overthrowing authoritarian rulers and for propping them up, for imposing its values on others and for caring only about oil—often by the same person, sometimes in the same sentence. In that moment of maximum media attention to any criticism, however self-contradictory, Scheuer released his book Imperial Hubris, under an anonymous byline, carrying only the information that the author was a senior official at the CIA.

The book instantly gained immense attention and praise. It helped that Scheuer had previously released (also anonymously) a more workmanlike book about al Qaeda’s ideology. Imperial Hubris was anything but workmanlike. It was positively coruscating, in ways that thrilled and amazed reviewers—and gained the book almost two months on the New York Times bestseller list.

Anonymity could not last long under such circumstances. Soon Scheuer was out of the CIA and on TV, amplifying the argument of his book. Osama bin Laden, Scheuer contended, was a hugely popular figure in the Muslim world: “the most respected, loved, romantic, charismatic, and perhaps able figure in the last 150 years of Islamic history.” Scheuer insisted that bin Laden’s views were shared “by a large percentage of the world’s Muslims across the political spectrum.” He utterly rejected the Bush administration’s claim that the United States was not at war with Islam. America, he wrote, must recognize that “much of Islam is fighting us, and more is leaning that way.”

The right way to think about al Qaeda, wrote Scheuer in 2004, was as a global Islamic insurgency. Suppressing so widely backed an insurgency would demand slaughter on an almost unimaginable scale: If U.S. leaders truly believed that the country is at war with bin Laden and the Islamists, they would dump the terminally adolescent bureaucrats and their threat matrix and tell the voters that war brings repeated and at times grievous defeats as well as victories, and proceed with relentless, brutal, and yes, blood-soaked offensive military actions until we have annihilated the Islamists who threaten us, or so mutilate their forces, supporting populations, and physical infrastructure that they recognize continued war-making on their part is futile.

Fortunately, continued the 2004 Scheuer, such violence was unnecessary because there existed a viable alternative policy: figure out what the terrorists want, and give it to them.

First, the end of all U.S. aid to Israel, the elimination of the Jewish state, and in its stead the creation of an Islamic Palestinian state. Second, the withdrawal of all U.S. and Western military forces from the Arabian peninsula—a shift of most units from Saudi Arabia to Qatar fools no Muslims and will not cut the mustard—and all Muslim territory. Third, the end of all U.S. involvement in Afghanistan and Iraq. Fourth, the end of U.S. support for, and acquiescence in, the oppression of Muslims by the Chinese, Russian, Indian, and other governments. Fifth, restoration of full Muslim control over the Islamic world's energy resources and a return to market prices [sic], ending the impoverishment of Muslims caused by oil prices set by Arab regimes to placate the West. Sixth, the replacement of U.S.-protected Muslim regimes that do not govern according to Islam by regimes that do.

In the context of 2004, that kind of talk passed for hard-headed thinking. Scheuer aired his views first to CBS News, then on Fox News when his CBS contract lapsed. The longer he remained in the public eye, the more he emphasized one particular theme in the book that made him famous: that it was Israel and the Jews who were to blame for America's difficulties in the Islamic world. By 2008, Scheuer was arguing that “Israel Firsters” started the Iraq War. In 2009, Scheuer was sacked by the think tank at which he then worked for denouncing President Obama’s choice of Rahm Emanuel as chief of staff, damning Emanuel as “a U.S. citizen who during the 1991 Gulf War left America to serve in Israel’s military.” (Emanuel in fact worked as a civilian volunteer in Israel during the Gulf War )

The language became progressively more bold and accusatory. The relationship with Israel cost America “blood and lives.” Israel “owns Congress.”

In 2012, while Michael Scheuer was campaigning for Ron Paul, a commentator named “Mike’ contributed the following to a Ron Paul forum.

I think Fox television would be missing a bet if it did not create a program called “Let’s Kill U.S. Kids and Bankrupt America.” The show could feature [Gary] Bauer, Charles Krauthammer, Bill Kristol, and John Bolton explaining why America needs more and more wars and why the president is above the Constitution and can legally take the country to war without a declaration of war by Congress.

In a subsequent interview with Ron Paul supporters, Scheuer confirmed that he was indeed the “Mike” who believed that his Fox colleagues wanted to kill kids and bankrupt America—and that his relationship with Fox had ended as a result.

And so, bump bump bump, all the way down.

America is a big country, and as such it contains a lot of everything, including a lot of people of intemperate, extreme, and bigoted views. In the era of modern media, these people have more opportunity to discover each other and to express themselves ever before. That’s the price of progress.

The good news is that the marketplace of ideas works. False claims (“bin Laden is hugely admired in the Islamic world”) retreat in the face of contrary evidence. Crackpots eventually reveal themselves as such, and forfeit their influence in consequence.

The bad news is that charlatans are often able to extend their influence with the influence of partisans who should know better, but who find the charlatans’ charlatanism politically convenient. Over the past five years, Democrats have become excruciatingly sensitive to Republican abuses of this kind. But there was a time, and it wasn’t so long ago, when liberal critics of the Bush foreign policy made similar common cause with a long roster of dubious characters: Karen Kwiatkowski, Juan Cole, John Mearsheimer… why it seems only yesterday that Ron Paul himself could count on a friendly hearing at MSNBC.

Partisans are seldom over-squeamish about their choice of allies. “He may be a crank/crook/bigot, but he’s an effective crank/crook/bigot"—is a line of reasoning that would have been as familiar to James Monroe as to any modern politician. Yet it is a line of reasoning with some nasty terminuses, not merely for the partisan who follows it, but for the political system as a whole. Instead of arguing over whose hands are dirtier, maybe it’s time to begin to worry about how all our hands might begin to be cleansed.