THE ARIZONA massacre suggests that the level of political discourse in this country has become too fevered . . . if only because most of the response to the shooting has been to assign political motives to this crime.

But right now, there is no evidence that Jared Lee Loughner was anything more than a sick and twisted individual who shares more similarities to other deranged people who have made successful or unsuccessful attempts on high-profile political figures - like Lee Harvey Oswald, John Hinckley, Arthur Bremer, Sirhan Sirhan - than to those figures, elected or otherwise, who have been cranking up the political rhetoric machine for the past few years.

The tragedy that felled six and injured 14, leaving Arizona Rep. Gabrielle Giffords critically injured, is the kind of shock to the system that leaves us looking for rational and straight lines from cause to effect. Hence, the fevered theories that have implicated tea partiers, Glenn Beck and Sarah Palin - for her website's use of crosshairs and her "lock and load" exhortations. These may be convenient, and even deserved, stops along the journey to the truth, but the line to such violence is rarely straight, and rarely rational.

As Ross Douthat pointed out Sunday in the New York Times, "violence in American politics tends to bubble up from a world that's far stranger than any Glenn Beck monologue - a murky landscape where worldviews get cobbled together from a host of baroque conspiracy theories, and where the line between ideological extremism and mental illness gets blurry fast."

Loughner was a follower of a conspiracy theorist who believes that an ancient race of reptiles secretly controls humanity.

Amid the response yesterday to the shootings was a proposal by U.S. Rep. Rep. Bob Brady, D-Pa., who says he wants to introduce legislation to make it a crime to direct violent or threatening words or images to a member of Congress.

Before we start limiting speech, we think

it would be far more useful to look at the other Brady Bill: The Brady Handgun Violence Prevention Act.

That act, which followed an attempt on President Ronald Reagan's life, requires that background checks be conducted on individuals before they can buy a firearm from a federally licensed dealer, manufacturer or importer, unless an exception applies.

Despite his obvious troubles, Loughner didn't have a criminal record, so he was easily able to get a gun. And what a gun: He used a Glock 9mm pistol, modified with a high-capacity magazine that fires 33 rounds. These types of high-capacity magazines were outlawed by the 1994 assault-weapons ban. That ban expired in 2004.

THAT ALLOWED HIM to convert his rage from a single shot that might have missed his target into a deadly bloodbath whose victims included a 9-year-old girl.

If any rhetoric can be blamed for this weekend's tragedy, it's the rhetoric that insists that gun control means an assault on people's constitutional rights, and that we need only to enforce the gun laws we already have. *