In May 2010, a radicalized Pakistani immigrant named Faisal Shahzad loaded his SUV with explosives and parked it in Times Square for detonation. Shahzad’s ambition, to kill Americans as vengeance for the war on terrorism, was thwarted by three street vendors who told cops about a car that was mysteriously smoking. One of them was a Senegalese Muslim immigrant named Alioune Niasse. Niasse did everything a conscientious person ought to do—he saw something and he said something—and yet his example factored not at all to a Long Island congressman who looked at Muslims like Niasse and saw terrorists in disguise.

That was Peter King, the three-decade Capitol Hill veteran who announced his retirement on Monday. While King had stiff competition, no legislator did more to demonize American Muslims than he did. Long before there was Donald Trump, there was Peter King.

King encouraged law enforcement spying in mosques, an invasion that no religious group in America would ever tolerate, when he wasn’t complaining that America hosted too mosques in the first place. He fanned the flames of anti-Muslim hysteria over an Islamic cultural center near Ground Zero. With a chairman’s gavel in his hand, King legitimized anti-Muslim persecution by holding a series of hearings resting on the bigoted and false premise that American Muslims were insufficiently committed to thwarting terrorism. (One 2011 study found that more than 20 percent of federal cases targeting Islamist terrorism began with tips from Muslims or with the cooperation of suspects’ relatives.)

The lasting achievement of King’s career was to portray millions of Americans as disloyal and threatening based on their religion, which would have been recognized as fundamentally un-American had his targets been white and Christian. But King won. His open demonization of American Muslims blazed a trail down which Trump marched to power.

“Good riddance,” Madihha Ahussain of the civil-rights group Muslim Advocates said in a statement. “The disappointing normalization of Peter King’s hateful legacy in Congress shows how deeply ingrained anti-Muslim bigotry has become in our politics.”

“ Good riddance. The disappointing normalization of Peter King’s hateful legacy in Congress shows how deeply ingrained anti-Muslim bigotry has become in our politics. ” — Muslim Advocates’ Madihha Ahussain

King was no passive participant in that normalization. He was one of the leading politicians to turn the anti-Muslim subtext of the war on terrorism into the explicit text of a war without end. In 2004, a period when George W. Bush’s White House was formally committed to rejecting a war on Islam, King called Muslims “an enemy living amongst us.” Even the “average Muslim” whose loyalty King purported not to question, “won’t turn in their own. They won’t tell us what’s going on in the mosques.” Unless Muslims became informants en masse—something the FBI cultivated through coercion—King felt free to question their patriotism.

By 2007, King contended there were “too many mosques in this country.” When a brief outrage ensued, King insisted he was taken out of context, as he had merely been trying to express that “too many mosques in this country do not cooperate with law enforcement,” as if that slander—for which he never felt pressure to defend with evidence—was somehow exculpatory. In an interview with Sean Hannity, King insisted baselessly that “extremist leadership” controlled 85 percent of American mosques, a talking point of King’s for so long that sometimes it would become 80 percent.

King’s view of Muslims expanded into the conservative mainstream. A 2010 attempt by a New York imam to establish an Islamic version of the 92nd Street Y, a Jewish center that forms a pillar of the city’s civic life, prompted a furious anti-Islam backlash as the “Ground Zero Mosque,” complete with demonstrator placards showing blood dripping from the word SHARIA. King cheered it on. New York’s Democratic governor, accommodating the outrage, sought to meet with the developers to show, in King’s words, where other “state property” is available for construction “whether or not people from the mosque would be willing to consider that property.” By September, King attended the protests against the community center. “Yes, we have to be sensitive to other people’s religions, but those religions also have to be sensitive to the memory of those who died on September 11,” he told rally-goers.

King spread innuendo on Fox News that “we don't know where the funding has come from; we don't know the full background of the mosque.” In fact, it was the brainchild of Imam Faisal Abdul Rauf, who since 9/11 had made it his mission to reconcile America and Islam. The bourgeois Rauf was the furthest thing from the “extremist leadership” King had denounced. Rauf had movingly memorialized slain Jewish Wall Street Journal reporter Daniel Pearl at an Upper West Side synagogue by declaring, “Today, I am a Jew; I have always been one.” But when the State Department announced plans to send Rauf to the Middle East to promote religious freedom, something that Rauf had done for the U.S. before, King called it “unacceptable.”

The Ground Zero Mosque backlash had real and violent consequences. A community board meeting became packed with protesters yelling that the community center was a “shrine to the very ideology that inspired the attacks of 9/11,” a flagrant attribution of collective guilt. One of the developers in attendance called it “the scariest thing I’ve ever seen in my life.” Ahmed Sharif was a Bangladeshi immigrant who drove a cab to support his four children. During the summer of the protests, one of Sharif’s passengers, a drunk NYU film student, demanded to know if he was a Muslim before taking out a Leatherman knife to stab Sharif repeatedly.

But King was only getting warmed up. The historic GOP victory in the 2010 congressional elections gave him the chairmanship of the House homeland-security committee. King used it to invite American Muslims to prove their loyalty. In March 2011, over furious objections from civil-rights groups, King a hearing titled “The Extent of Radicalization in the American Muslim Community and That Community's Response,” the first in a series of hearings that legitimized Islamophobia on Capitol Hill.

It was a watershed moment. King invited witnesses, often nonwhite, who blamed Islam for the deaths or the radicalizations of their children. One father of a jihadi convert lamented his son taking “the picture of Dr. Martin Luther King Jr off the wall… only the Islamic cultural [sic] mattered to him.”

For his own part, King demanded that “moderate leadership must emerge from the Muslim community,” taking it upon himself to reject the leadership that actually existed. He toggled between considering American Muslims prey for al Qaeda and indistinguishable from al Qaeda itself. One witness from Human Rights First referenced Alioune Niasse’s role in stopping the Times Square bombing, but it made no difference. King instead raged against those who pointed out the McCarthyism of his hearings, saying backing down would be a “flagrant surrender to political correctness.” The same held for expanding his critique of domestic radicalization to non-Muslim extremism. “There is no equivalency of threat between al Qaeda and neo-Nazis,” King insisted. His words ring out after Mother Emanuel, Charlottesville, Pittsburgh’s Tree of Life synagogue, the Christchurch mosque slayings and innumerable other white supremacist atrocities.

But King was never bothered about terrorism committed by people with white skin or Christian backgrounds. Before his election to Congress, King, an Irish-American, practiced the same sort of “extremist leadership” he would later attribute to Muslims. He said that if an Irish Republican Army attack killed civilians, “it is certainly regrettable, but I will not morally blame the IRA for it.” He raised money for the IRA’s American fundraising adjunct in the 1980s, something that leading civil-libertarians noted would have gotten King prosecuted for material support for terrorism had he done it after 9/11.

Through it all, King, eventually a member of the intelligence committee, acted as if mass persecution was common sense. He demanded in 2013 that Boston marathon bomber Dzhokhar Tsarnaev be held as an enemy combatant; Tsarnaev was swiftly convicted at trial and sentenced to death. The next year, after a terrorist attack in Ottawa, King demanded law enforcement go “all out with surveillance” and “monitor what’s happening in those [Muslim] communities.” In 2015, King said that “infiltrating” mosques “has to be done” since “you look where the terror threat is going to come from and right now it is going to come from the Muslim community.”

By then, King was no longer a marginal figure. He prefigured the nationalist direction conservatism took. Candidate Donald Trump, ratcheting King’s rhetoric a step further, said there was “absolutely no choice” but to close down mosques in America; flirted with enacting a national database of Muslims; and pledged to ban Muslim immigration to the United States. King, who flip-flopped on Trump during the primaries, saw his vindication. When Trump was elected president, King urged him to drastically expand surveillance on Muslims and take an NYPD spying program — one that saw the police pay damages to surveillance victims — national. When Trump issued his Muslim-focused travel ban, King enthused that the measure was “overdue.”

It is a testament to how cheaply mainstream American politics has come to value Muslim lives that King’s career lasted as long as it did. When King announced his retirement, the top Democrat in the Senate, New York’s Chuck Schumer tweeted that he will miss King, a man who “stood head & shoulders above everyone else” and who “never let others push him away from his principles.” Those principles were the second-class citizenship of American Muslims. With the enthusiasm of many and the acquiescence of more, King pushed that un-American principle out from the fringes and into the White House.