Fifteen years ago today, militia sympathizer Timothy McVeigh blew up a truck full of explosives at the Alfred P. Murrah Federal Building in Oklahoma City, killing 168 people and wounding more than 600 in the worst terrorist attack to hit the United States before 9/11. And for more than a few observers, there’s a smell similar to 1995 hanging in the air today. In her Sunday Washington Post column, Kathleen Parker asked, “Is the political environment becoming so toxic that we could see another Timothy McVeigh emerge?” This morning, blogger Steve Benen wrote, “For those of us who follow American politics closely, the developments are common enough to become dizzying.” And in the New YorkTimes, Bill Clinton just reminded us that, “In the current climate, with so many threats against the President, members of Congress and other public servants, we owe it to the victims of Oklahoma City, and those who survived and responded so bravely, not to cross [the line crossed in Oklahoma] again.”

Indeed we do. But few analysts have ever acknowledged that Clinton himself was resurrected by the bombing. That McVeigh murdered 168 Americans is only part of his legacy: He also detonated his own fringe, and the aftermath of Oklahoma City should stand as a lesson to politicians on both sides of the aisle.

Exactly 15 years ago yesterday, then-President Clinton was forced to declare at a press conference, “I’m relevant. The Constitution gives me relevance.” Health-care reform was dead, and Hillary Clinton seemed discredited. Both houses of Congress had gone Republican, and the GOP was rolling out its legislative plans.

The next morning, the Oklahoma City Federal Building exploded. Pundits would go on to write that it was the government shutdown later that year that allowed Clinton to trump the Republicans, but it was actually Oklahoma City that first allowed him to step forward as a national leader. As speechwriter Michael Waldman wrote in his book POTUS Speaks: “It was the nation’s first exposure to Clinton as mourner in chief … In fact, it was the first time Clinton had been a reassuring figure rather than an unsettling one.”

Even more than that, Oklahoma City created a huge political opportunity, which Clinton quickly seized. On April 27, a little more than a week after the bombing, Dick Morris, then a little-known but influential Clinton adviser, presented the President a fantastically naked political memo that, as you can find in his book Behind the Oval Office: Getting Reelected Against All Odds, said: “Permanent possible gain: sets up Extremist Issue vs. Republicans.” Morris suggested using “extremism as issue against Republicans,” not by “direct accusations,” but via a “ricochet theory.”

Clinton should “stimulate national concern over extremism and terror,” Morris wrote, and then “implement intrusive policy against extremist groups.” Morris predicted that radical right-wingers would write their local Republican congressmen, and that in turn “this will provoke criticism by right-wing Republicans which will link right-wing of the party to extremist groups.”

“Net effect,” Morris concluded: “Self-inflicted linkage between party and extremists.”

The Clinton Justice Department didn’t go as far as Morris wanted, but it didn’t matter. Republican members of Congress soon made fools of themselves defending militias. And Clinton found his voice. At a Michigan State commencement address shortly afterward, he told graduates, “There is nothing patriotic about hating your country, or pretending that you can love your country but despise your government.”

In his memoirs, Clinton didn’t mention the Morris memo, but wrote: “The haters and extremists didn’t go away, but they were on the defensive, and, for the rest of my term, would never quite regain the position they had enjoyed after Timothy McVeigh took the demonization of government beyond the limits of humanity.” Indeed, Oklahoma City gave Clinton the chance to pull his presidency together by advancing a positive agenda of triangulated social issues. And that strategy reached full flower in his 1996 State of the Union speech, where Clinton introduced a man named Richard Dean, a Vietnam vet who had worked in the Oklahoma City Federal Building and who re-entered the building four times to rescue people after it blew up. As everyone, including Republicans, stood to applaud, Clinton went on:

But Richard Dean’s story doesn’t end there. This last November, he was forced out of his office when the government shut down. And the second time the government shut down, he continued helping Social Security recipients, but he was working without pay … I challenge all of you in this chamber: Never, ever shut the federal government down again.

That’s how much Clinton got it: He explicitly linked the terror of Oklahoma City to the federal shutdown, and both to the Republican Congress. After that, Clinton barely needed to look over his shoulder to get reelected.

These days, Republicans are allowing the likes of Michele Bachmann and Rush Limbaugh to speak for the party, while Newt Gingrich is talking about shutting down the federal government all over again. GOP leaders are unwilling to denounce the “lunatic right” on their merits. Today is a day to remember how terribly that ended before.