A 2016 survey found that 70 percent of Americans believe incivility has reached crisis proportions. A 2015 poll found that 68 percent of Americans believe that “a big problem this country has is being politically correct.”

These polls suggest tremendous American uncertainty about where proper manners leave off and its extremes—incivility and political correctness—begin. That uncertainty, unfortunately, fuels America’s growing tribal sense that if what I say offends you, you are being politically correct. If what you say offends me, you ought to be fired.

Respondents to the 2016 poll primarily blamed politicians for growing incivility, but they also complained about the media, rude cellphone behavior and cursing.

The proliferation of profanity, much of it provoked by rude cellphone use, is so obvious that it scarcely needs elaboration. Even the breakdown in political civility is hard to miss. In less than five minutes of listening to Rush Limbaugh on Tuesday, I heard him call federal judges on the 4th Circuit “stupid,” refer to a Supreme Court justice as Ruth “Buzzi” Ginsburg and label the Democratic Party as a “hate group.” So routine is such invective that the world will scarcely notice.

But a bucket full of examples that test our tribal instincts have recently come our way. Greg Gianforte’s uncivil assault on a reporter was defended by some of his supporters. Comedian Kathy Griffin lost a hosting gig with CNN for a video in which she held up what appeared to be the decapitated and bloody head of Donald Trump. On Friday night, calls began to go out to fire Bill Maher for saying the “N-word” on his “Real Time” show on HBO.

Just on Monday, 10 students accepted to Harvard had their admissions rescinded because of racist and hateful comments made on a private social media group. Even conservative stalwart Breitbart News just fired a reporter for inflammatory and racist tweets.

Almost everybody agrees that at least some of these incidents cross the line. The problem is that nobody can agree on exactly where the line is. We have one line for newspapers, another for broadcast television, still another for cable TV, another for movies, another for Facebook. And now, at last, one for conservatives and one for liberals.

Gianforte’s supporters presumably have a line they would not cross, even if they don’t know where it is. If it’s OK to attack reporters with fists, is it OK with a knife? Or a good old, Second Amendment-guaranteed, Montana hunting rifle?

Almost nobody defended Griffin for her disembodied symbol. But many noted that rock star (to use the term loosely) Ted Nugent has expressed equally vile thoughts about liberal politicians. He called Barack Obama a “subhuman mongrel” and a “piece of shit” who should “suck on my machine gun.” He called Hillary Clinton a “worthless bitch” and said she should be hanged. He called Sen. Dianne Feinstein a “worthless whore.” He also said some things that I am reluctant to repeat even at Last Best News.

Nugent’s reward? A visit to the White House and a posed picture with the new president.

I’m only vaguely familiar with Griffin’s work, but I’m a big fan of Bill Maher’s show. He says something offensive just about every week, but he also is a funny guy who isn’t afraid to take on guests who not only disagree with him but often outsmart him. It’s one of the few shows built on political commentary that actually deals with fundamental questions and real issues.

Dropping another word I am too gutless to print into a conversation on live television was a bad idea, which Maher realized almost immediately and apologized for. Offensive though the word may be, he clearly did not intend it as a slur. He was mocking the idea of slavery, not celebrating it, so I find it easy to forgive him.

It’s too easy to blame all of this on the Blasphemer in Chief, who stirred the pot of incivility himself this week by criticizing the mayor of London following last weekend’s terrorist attacks. Not only did Trump take the mayor out of context, he doubled down on his attack when the mayor said he didn’t have time to waste on the president’s ill-informed tweets. As usual, Trump had no evidence to offer for his claims except his own bile.

Beyond political leanings, there’s just no predicting exactly what pushes the button that turns a minor offense into a public outrage. I have a professional interest in protecting the right of reporters to ask questions without getting beat up, so my reaction to Gianforte’s uncivil behavior surprises no one. But more than any of the other offenses that made the news in the last week, I was most offended by a Billings Gazette editorial about the Griffin gaffe that contained this paragraph: “Griffin cannot joke with a prop so hackneyed it’d make even the Marx Brothers blush at its amateurish attempt.”

“Even” the Marx Brothers? Now that hurts. The brothers, excepting maybe Gummo, were the premier comic geniuses of the 20th century. They bumped up against the Hays Code and every other code governing civilization with a nonstop stream of double entendres, salacious jokes, slapstick humor and arched eyebrows. “Monkey Business” was banned in Ireland out of fear it would stir up anarchy. “Duck Soup,” the Marx Brothers’ 1933 sendup of war and diplomatic bungling, was banned by Mussolini, Italy’s trumped-up version of a Depression era national leader.

Groucho Marx, hurling insults all the way to the grave, and his brothers died as culture heroes. It was a simpler time, I suppose. But they had a way of defusing anger at their offenses, conveying a sense that it was all in good fun and everybody takes a turn as the butt of public ridicule. Don’t like that joke? Hang on, here comes another one.

At its base, maybe it was just good manners.

David Crisp is a longtime Billings journalist and college professor. He writes a weekly column for Last Best  News.