This shouldn’t have to be said again, but unfortunately it has become necessary: Sadly, amid all the criticisms of figures in public life that now surround us, it would be a great advance in civility simply to stop using violent images about harming or even killing people with whom we disagree.

Yes, it’s been said before. And no, it hasn’t made much of a difference.

A pair of recent examples prove the point, although they are only two among many on all sides of the current political debate.

First, rock musician and gun rights backer Ted Nugent, a right-wing activist of the purest sort, earned himself a fully justified visit from the Secret Service last week.

He had told attendees at the National Rifle Association’s annual meeting earlier this month that, because the Obama administration was “vile, evil and American-hating,” people needed “to ride onto that battlefield and chop their heads off in November.”

He added that if Obama is re-elected, “I will either be dead or in jail this time next year.”

It doesn’t stretch the imagination too much to find those statements cause for concern. The Secret Service has apparently satisfied itself he didn’t mean any real harm by them, but it’s hard to tell without checking.

In addition, a Democratic state legislator here in Maine also said he meant no actual harm by a tweet he sent last year that could be easily interpreted as a death wish for former Vice President Dick Cheney.

Rep. Chuck Kruger of Thomaston tweeted that “Cheney deserves same final end he gave Saddam. Hope there are cell cams.” Since the former Iraqi dictator was hanged, the implication seemed clear. Kruger later apologized, and said that he had received what he said were “two death threats” in response. Those should be investigated and, if genuine, prosecuted.

But our politics would be greatly improved if all of us refrained from using words like these.