The Russian playwright Anton Chekhov had a rule: if you show a gun in the first act, by the time the curtain falls, it has to go off. For weeks and months, that gun, the weapon of angry rhetoric and intemperate rabblerousing, has been cocked and loaded in plain view on the American stage; Saturday morning outside a shopping mall in Tucson, Arizona, it went off again and again and again.

The target, Gabrielle Giffords, a member of the United States Congress, lays critically wounded, one of thirteen shot and still alive. Six others are dead, including a respected Federal judge who happened to be there but who previously had received death threats from anti-immigration extremists, a member of Congresswoman Giffords’ staff and a nine-year old girl, Christina-Taylor Green. Just elected to her school’s student council, she had been brought by a neighbor to Congresswoman Gifford’s constituent event so she could see how grown-ups put democracy into action.

Instead, this child – born on 9/11 -- became just one of the latest victims of more political violence in America, violence fueled by an incoherent rage against government and elected officials who cannot instantly bring back prosperity and the jobs lost overseas or restore in a blink some idealized vision of a nation that might once have been but is no more. And all of it egged on by right wing leaders and their cronies lurking in the swampier reaches of the Internet, hate radio and television

We now see the deadly effect. The root causes are many and less distinct: fear of the future and what it may or may not hold, hostility inflamed by the economic injustice and uncertainty that force too many to live from paycheck to paycheck without anything saved or the slightest guarantee of security -- a gnashing of teeth and sharpening of claws because others may have what you have not. Or this: the simple fact that there are just too many damned guns in this country. One in four Americans owns at least one. The NRA would order gun racks in the cradles of newborn infants if they could. Too many weapons are used not for hunting or target shooting or legitimate protection, but for combating feelings of inadequacy and weakness with fantasies of firepower -- fantasies that crazed gunmen too often try to make reality. That someone like Jared Lee Loughner can walk into a store and buy a weapon that fires 30 rounds a clip is probably not what the Founding Fathers had in mind when they talked about "a well-regulated Militia being necessary to the security of a free State."

No one can prove that the vitriolic talk from the right was in the killer's mind as he carried out his attack, but no one can prove it wasn’t, either. So in the absence of evidence to support either side, why doesn't the right just volunteer to put an end to all the ballistic language and images it's been employing for many years now? Why not cease and desist if there's any doubt about the impact on lunatics of provocative violent-saturated words and images? Sarah Palin must have suddenly felt queasy about those crosshairs over Giffords’ congressional district that were still up on her website, because the mama grizzly, half-term governor took them down soon after the violence (although as of this writing they were still on her Facebook page). But then she sent an aide to do a radio show in which she agreed with the sympathetic interviewer that the crosshairs were more like “surveyors’ symbols”! Why prolong that kind of stuff? Why not just knock it off and apologize or simply shut up?

The fact is, it has been the right's goal to poison our political discourse for years. Remember the notorious “GOPAC Memo” back in the 1990’s, created for the Republicans’ leadership training institute and endorsed by Newt Gingrich? Titled "Language: A Key Mechanism of Control,” in it, candidates are instructed in what words to use when defining their opponents (i.e., liberals). "These are powerful words that can create a clear and easily understood contract,” the memo said. “Apply these to the opponent, their record, proposals, and their party” (in other words, demonize them).

Among them: intolerant… lie… pathetic… radical… sick… steal… traitors. Gingrich and his allies deliberately set out to employ toxic language against their opponents, and are still doing it. They will say anything to get a vote, especially now that the angriest and most irrational so often make up a majority of those who bother to go to the polls. This kind of talk is part and parcel of their strategy, and no matter what motivated the Tucson killings, it needs to stop.

Their lock and load rhetoric is reinforced by the rambling ranks of those who go on the Internet to spout any conspiracy theory, distortion of history or outright lie that helps them make it through the night. Add, too, the men and women of radio and television, the Limbaugh’s, Beck’s, and their ilk who use the airwaves as a cudgel, battering viewers and listeners with the certainty of their illogic, their thinly veiled messages of bigotry and meretricious embrace of Constitution, religion, flag and family.

All of them will huff and puff that this is an isolated incident by a madman that cannot be blamed on their bombast and bluster. But let’s call it out for what it is, let’s debate what in our gut we know to be true: even if it was not their intent, it’s likely the words of the right on radio and TV and in the books they publish spurred on the man who killed two and wounded six in a Knoxville, Kentucky, church in July 2008, and the murderer of George Tiller, one of the few doctors in America who still performed late-term abortions for women with problem pregnancies whose health was at stake from life-threatening complications, or whose infants would be born dead or dying. Their invective, whether inadvertently or not, has encouraged the vandalism and threats faced by so many of our candidates and elected officials, including the now desperately wounded Congresswoman Giffords. Her shooting, and the death and wounding of so many who came to meet with her are just the latest example of ideologically-motivated bloodshed.

“Let me say one thing,” said Clarence Dupnik, sheriff of Pima County, Arizona, where the shootings took place, “because people tend to pooh-pooh this business about all the vitriol that we hear inflaming the American public by people who make a living off of doing that. That may be free speech, but it’s not without consequences.” He singled out radio and TV and said, “When you look at unbalanced people, how they respond to the vitriol that comes out of certain mouths about tearing down the government, the anger, the hatred, the bigotry that goes on in this country is getting to be outrageous.” An elected Democrat, he was immediately attacked by Republicans and the right, his statements dismissed as partisan and inappropriate.

"The facts weren't even out there, Rep. Giffords had been carted away in a stretcher, we didn't even know her condition, but the war had already started. The folks on the hard left were already out there blaming the tea party." So complained Judson Phillips, founder of Tea Party Nation. He told The Washington Post, "If we ever needed an official political obituary to political civility in this country, we've seen it.”

Mr. Phillips, that obituary was written long ago, thanks to you and your friends. Enough.

Michael Winship, senior writing fellow at Demos and president of the Writers Guild of America-East, is senior writer for Bill Moyers' new weekend show Moyers & Company.

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