Why do some pro-life extremists murder abortion doctors? Because they believe those doctors kill babies and should be repaid in kind. Yet, I don’t know anyone Right or Left, including the overwhelming majority of pro-lifers, who finds the murder of doctors anything less than horrendous.

Why do some Black Lives Matter extremists go on cop-killing rampages? Because they believe the police are killing black men and women wantonly, and should be repaid in kind. Yet, I don’t know many people Left or Right, including the majority of anti-police brutality activists, who find the murder of law enforcement officers anything less than despicable.

I’m pro-life and anti-police brutality, but can’t fathom resorting to violence — committing violence in the name of stopping violence — to “further” my political cause. Most people wouldn’t.

But some, particularly the mentally disturbed, might.

This was precisely what Sen. Rand Paul, R-Ky., was talking about recently when he worried that a political figure could get assassinated in the current tense political environment. "I really worry that someone is going to be killed and that those who are ratcheting up the conversation ... they have to realize that they bear some responsibility if this elevates to violence," Paul said .

[Opinion: The violent Left is a serious problem, stop parroting their propaganda]

Recalling the 2017 incident at a Republican baseball practice in which a deranged man opened fire, shooting five people including House Majority Whip Steve Scalise — and where Rand Paul was also present, hiding behind a tree to avoid getting struck by a bullet — the senator said, “These are people that are unstable. We don't want to encourage them. We have to somehow ratchet it down and say we're not encouraging them that violence is ever OK.”

The senator believes some of the rhetoric of his fellow senators, including his ally on criminal justice reform , Sen. Cory Booker, D-N.J., has been guilty of such language. “I think what people need to realize, that when people like Cory Booker say ‘get up in their face,’ he may think that that's OK,” Paul said. “But what he doesn't realize is that for about every thousandth person that might want to get up in your face, one of them is going to be unstable enough to commit violence.” Booker’s office has said that his comments had been taken out of context.

The Kentucky senator’s wife, Kelley Paul, recently penned an op-ed explaining, “ My husband, Rand Paul, and our family have suffered intimidation and threats ,” in which she revealed that she now sleeps with a loaded gun out of fear in the current political environment. Recounting two assaults against her husband last year, the baseball shooting and a well-publicized physical attack by the senator’s neighbor, Mrs. Paul wrote, “Earlier this week, Rand was besieged in the airport by activists ‘getting up in his face,’ as you, Sen. Booker, encouraged them to do a few months ago.”

“Preventing someone from moving forward, thrusting your middle finger in their face, screaming vitriol — is this the way to express concern or enact change?” Mrs. Paul asked. “Or does it only incite unstable people to violence, making them feel that assaulting a person is somehow politically justifiable?”

This is a legitimate concern. The Paul family is right that leaders should be more careful with their words. In addition to what Booker may or may not have meant, Rep. Maxine Waters, D-Calif., has been accused of calling for political violence in recent months. Hillary Clinton said this week , you “can’t be civil” with Republicans.

[Trump on Hillary Clinton's rejection of civility: 'That's why she lost']

Okay, Mrs. Clinton and anyone else, Left or Right: If we can’t be civil in our politics — what’s next? What is the next logical step?

What do crazy people hear in such a declaration?

Recall the recent history of the debate over political civility. In 2011, when a deranged gunman shot Rep. Gabrielle Giffords, D-Ariz., in the face, media pundits were quick to blame Republicans and especially Tea Party darling Sarah Palin, whose PAC had “ targeted ” Democratic districts including Giffords — as if “targeting” candidates for electoral defeat hadn’t been a part of conventional political speak since forever. These liberal pundits could have just as easily blamed any of the local Target retail stores in Giffords’ district (not to mention, the shooter could have been simultaneously described as much far-left as far-right ).

Yet, this outright lie about Palin was told over and over as an article of faith by the Left, and as late as 2017 by the New York Times , prompting Politifact to remind the Gray Lady that it was still false .

Still, what Democrats were accusing Palin of seven years ago wasn’t an explicit call to arms or even getting up in people’s faces. It was just critics of the Tea Party eager to connect dots that weren’t there.

Today, prominent Democrats are saying forthright that civility is impossible and that it’s time for the Left to get “ tougher .”

American politics unquestionably continues to dangerously devolve.

Think about it: How often did Democrats ( rightly ) take President Trump to task for his irresponsible rhetoric that could lead to potential violence? In particular, the president’s comments about there being “ very fine people on both sides ” and “ blame on both sides ” during the white supremacist rally in Charlottesville, Va., in 2017. At at that rally, anti-racist activist Heather Heyer was killed by an extremist. Trump, although likely unintentionally — just as Booker, Waters, or Hillary Clinton are likely unintentionally reckless in their rhetoric — still gave moral authority on some level to those who sought violence. Such rhetoric encouraged violence more than it tamped it down.

No responsible leader, Republican or Democrat, can afford to do that.

Bringing up Heyer’s death is how many on the Left decided to dismissively respond to Paul’s calls for civility — “ Rand Paul says toxic politics is going to kill someone. It already has ,” read a Huffington Post headline — as if the senator had ever said anything remotely encouraging about that rally or its violent attendees. The senator’s chief adviser, Doug Stafford, even penned an op-ed for Time explicitly and forcefully denouncing the racists at the rally and their agenda.

Many liberals also dismissed Paul’s concerns over potential violence by citing a pro-Second Amendment tweet by the senator in 2016. “Why do we have a Second Amendment?” tweeted Paul's account, quoting Fox News’ Judge Andrew Napolitano. “It's not to shoot deer. It's to shoot at the government when it becomes tyrannical!”

Some on the Left lampooned the tweet, as if Paul was somehow advocating shooting at government officials at the same time he was concerned about “ assassinations .” As if the American Revolution — or if we’re going there, North Carolina NAACP head Robert F. Williams in the 1950s, who stockpiled guns as the Second Amendment allows to protect his black community from the Ku Klux Klan, many of whom were local politicians and police — was the same thing as a mentally ill Democrat firing at Republicans on a baseball field because he was mad about GOP efforts to repeal Obamacare.

The liberals mocking Paul’s pro-Second Amendment tweet actually unintentionally made his point for him: When mentally-unstable people can equate a political disagreement over Obamacare, or abortion, or police brutality, with something like the American Revolution or a black man living in the Jim Crow South trying to protect his own people from the local authorities (whether wearing white hoods or otherwise), just about any action can be justified, including violence.

When partisans begin to envision every political disagreement as a moral crusade, that’s dangerous for any liberal society. When unstable people take those same cues, it’s not hard to see how they rationalize the use of violence.

This is the logic of terrorists. Resorting to violence by targeting innocents (or are theses figures really innocent? Which is also the logic of terrorists) to supposedly advance an ideological or religious agenda is how terrorists of any stripe think, from the men who flew planes into the World Trade Center on Sept. 11, to the angry young white supremacist who walked into a black church in Charleston, S.C., in 2015 and murdered nine innocent men and women .

But it’s also how too many regular Democrats and Republicans have begun to talk about our politics. That even violence at this point is okay, so long as it’s your political opponents who suffer. Many on the Left even supported Paul being assaulted by his neighbor this year, an act that if committed against former President Barack Obama or House Minority Leader Nancy Pelosi, D-Calif., undoubtedly would not have received the same leftist encouragement.

But that’s where we are right now. Rand Paul is right to be worried. All Americans should be.

"When they finally were able to kill him, in his pocket was a list of five or six conservative Republicans that he came there intending to kill," Paul said of James Hodgkinson, the 2017 baseball field shooter.

"Trump is a Traitor. Trump Has Destroyed Our Democracy. It's Time to Destroy Trump & Co." Hodgkinson posted online. Treason is punishable by death under the Constitution.

"Republicans are the Taliban of the USA," Hodgkinson also posted . America went to war against the Taliban.

If James Hodgkinson were still alive today, Hillary Clinton would be telling him and those like him that Democrats can’t be civil with Republicans.

He certainly wasn’t.

Jack Hunter (@jackhunter74) is a contributor to the Washington Examiner's Beltway Confidential blog. He is the former political editor of Rare.us and co-authored the 2011 book The Tea Party Goes to Washington with Sen. Rand Paul.

Correction: An earlier version of this column incorrectly noted that Paul himself was the source of the "Why do we have a Second Amendment?" quote.