It was not September 11 that made conservatives receptive to Gaffney’s theories. It was America’s failed post-9/11 wars. Joseph McCarthy won a following in the early 1950s, when Americans were exhausted by the stalemated war in Korea, by arguing that the real communist threat could be vanquished cheaply and nonviolently by ferreting out traitors at home. Gaffney argues something similar. “We can kill as many semi-literate bad guys as possible in the world’s most hellish backwaters,” he declared in 2012, “but as long as we ignore, or worse yet, empower and submit, to the toxic ideology they share with highly educated and well spoken Islamists in this country and elsewhere, we are doomed to defeat.”

Over the last decade, conservatives disillusioned by the wars in Iraq and Afghanistan, and alienated from their party’s interventionist elite, have found in Gaffney’s theories an appealing alternative. A key ally in that disseminating that alternative has been Breitbart. In March 2013, with Gaffney barred from speaking at CPAC, Breitbart hosted a series of panels called “The Uninvited” in the same hotel where the conference was being held. Steve Bannon moderated. The panels featured Gaffney and Pamela Geller, who had risen to prominence opposing New York’s “Ground Zero Mosque.” They offered a platform to conservatives who argued that the greatest threat to American security lay not in jihadist terrorism abroad but in Muslim subversion inside the United States.

The following spring, Breitbart sponsored “The Uninvited II: The National Security Action Summit.” Bannon offered welcoming remarks; Gaffney moderated. That fall, Bannon and Gaffney co-hosted yet another set of panels, entitled National Security Action Summit II. Since then, Breitbart has become Gaffney’s largest media megaphone. When The Washington Times cancelled his column, Breitbart picked it up. And Bannon interviewed Gaffney on his Breitbart radio show 29 times. Bannon has also echoed Gaffney’s core thesis: calling Islam “a political ideology,” likening Sharia to “Nazism, fascism, and communism,” and describing the Muslim Brotherhood as part of “a fifth column in this country.” On Bannon’s radio show in November 2015, Geller declared that, “Any mosque that advances, promotes, jihad must be shut.” Bannon replied: “Sedition, absolutely.”

If Breitbart was the first key institution to propagate Gaffney’s theories, Act for America was the second. Led by a Lebanese-born Christian named Brigitte Gabriel, ACT didn’t have a single paid employee in 2004. By 2016, it claimed 300,000 members and budget of more than $1 million.

ACT’s agenda closely parallels Gaffney’s. It uses the specter of the Muslim Brotherhood and Sharia law to depict American Muslim political participation, and even religious expression, as a security threat. ACT tries to ban the use of Sharia in American courts. It seeks to prevent the Council of American-Islamic Relations (CAIR) from lobbying state legislatures. It tries to remove from textbooks any references that equate Islam with Judaism and Christianity. It urges Jewish and Christian groups to eschew interfaith dialogue with Muslims. In the name of stopping Sharia, it even opposes the sale of Halal food. In 2007, a questioner asked Gabriel, “Should we resist Muslims who want to seek political office in this nation?” She replied, “Absolutely. If a Muslim who has—who is — a practicing Muslim who believes the word of the Koran to be the word of Allah … this practicing Muslim, who believes in the teachings of the Koran, cannot be a loyal citizen to the United States of America.”