We’re living through an interesting moment in modern politics. The left has not reacted well to the election of Donald Trump and has been decrying his violation of norms while also testing the waters for some norm violations of their own. But if the left is attracted to the idea of tossing norms aside to defeat Trump, they are also hesitant about what that might mean.

For instance, you have Rep. Maxine Waters calling for the harassment of everyone who works for Trump in private life. But you also have Sen. Chuck Schumer and Rep. Nancy Pelosi criticizing Waters for crossing a line. You have one far left activist throwing Press Secretary Sarah Sanders out of her restaurant but you also have some people who think that’s going too far. The radicals are behaving badly, but they haven’t quite convinced the leaders to join them yet, at least not in public.

There have been two pieces published by Politico Magazine in the past two days that hover on this question of just how far the left should take this. Yesterday, the site offered an endorsement of crossing the line by a political science professor named Rob Goodman. Goodman discusses a book by another political scientist who has argued the left should do whatever it takes to win and lock Republicans out of power, including packing the Supreme Court and creating several new states. The only caveat Goodman adds to this argument is that the left, or the part of it that is pushing for violating norms to win, should only cross this line if it’s sure it can follow through:

If the Normal Is Over caucus can imagine a unified, genuinely radical Democratic government in the next four or eight years, they’re also responsible for imagining an enraged opposition, strong in the conviction that the Democratic government is illegitimate. We saw exactly that the last time there was a Democratic government. And we can fully expect next time to be worse, because the culture of self-restraint is weakened with each iteration of the cycle.

This means that a strategy of Democratic norm-breaking is justifiable only if it can be reasonably expected to result in a lasting political realignment—to break the cycle rather than escalate it. It must so thoroughly disempower the other side that it forestalls serious reprisals. Put simply, the strategy that Faris and others on the left are proposing had better work—because the tit-for-tat conflict that would result from a halfhearted or incomplete attempt would be even worse than the status quo.

There’s a little nuance in his argument but not much. It basically boils down to the old adage that if you take a shot at the king, you better be sure you kill him. If you’re going to start breaking norms, you have to be all in. No doubt there are plenty of folks on the far left cheering that prospect on, but should they be?

Today, Politico posted a piece that takes a much dimmer view of the left embracing norm violation. It’s titled, “Here’s What Happened the Last Time the Left Got Nasty.” The gist of the piece is that Democrats were in a similar mood in the late 1960s and the results were not good:

Peaceful protests continued, but growing numbers of militants now styled themselves revolutionaries and adopted tactics to match. Groups like the Weather Underground preached and carried out violence, including lethal violence, which was deemed “as American as cherry pie” by H. Rap Brown, rendering ironic the name of the group he’d come to lead, the Student Nonviolent Coordinating Committee. (Brown, who now goes by Jamil Al-Amin, is currently serving a life sentence for murder.)

Most activists stopped short of planting bombs and shooting police officers. But many still blew past the boundaries of what nearly everyone considered legitimate protest. Demonstrators not only directed chants of “Hey, hey, LBJ, how many kids did you kill today?” at President Lyndon Johnson; they also accosted officials of his administration when they set out in public. In 1967, when Secretary of State Dean Rusk tried to attend a banquet of the Foreign Policy Association in New York, a radical group called Up Against the Wall Motherfuckers (often called “the Motherfuckers” for short) threw eggs, rocks and bags of cows’ blood, though Rusk slipped into the hotel unscathed. Defense Secretary Robert McNamara was spat upon in an airport and called a baby killer; on a visit to Harvard, a hostile mob encircled his car and rocked it back and forth until police spirited him to safety via a tunnel. Antiwar radicals even tried to set fire to McNamara’s Colorado vacation home—twice. A few years later, after he’d left government, someone tried to throw him off the Martha’s Vineyard ferry.

The article adds that this turn away from civility peaked after Nixon’s election.

A presidential study pointed to a national “crisis of violence,” with some 41,000 bombings or bomb threats during his first 15 months in the White House. In this context, the far left continued to directly go after members of the administration and even the first family. Various Nixonites recounted harrowing incidents in their memoirs or interviews. Daniel Patrick Moynihan, then a White House domestic policy aide, told Nixon in May 1970 that militants from Students for a Democratic Society had threatened to torch his Cambridge, Massachusetts, house, forcing his family to go underground. His 10-year-old son, John feared his father would be assassinated.

We’re already seeing some of this now. The families of both FCC Chairman Ajit Pai and Sen. Rand Paul have been threatened recently. That’s on top of the rash of threats last year against members of Congress. As of last June, the U.S. Capitol Police had investigated more threats against lawmakers in six months than they had in all of 2016. Ultimately, the author of the piece argues not that such behavior is wrong, but that it is ineffective:

The taunting of public figures isn’t well remembered, and neither will history long record June’s showdown at the Red Hen. But insofar as these actions stem from a determination to score political points by violating civil norms, they—and the repellent and violent methods of extreme protesters more generally—engender a backlash and alienate allies. By 1972, we should recall, a majority of Americans had come to oppose the Vietnam War, but greater numbers opposed the antiwar movement.

The left already has a toe, or maybe an entire foot, over the line but only now it seems to be hesitating a bit about going all in. It’s worth noting that both of the authors of the two pieces mentioned above are clearly on the left and anti-Trump. They aren’t interested in protecting the status quo, they are just worried that if the left goes all in they will a) enrage the right in a way that is unpredictable and b) drive up their own negatives and thereby harm their own cause.

I think the authors are right about that. The left is playing with fire right now because it imagines that only its opponents will get burned, but that’s not how things work in real life. The left may have convinced itself that all the boundaries of civility have been abandoned but they haven’t, not yet anyway. Things could get a lot worse if the left decides to go all in.