See Slate's complete coverage of the Gabrielle Giffords shooting and arrest of Jared Lee Loughner.
In response to Jared Lee Loughner's shooting spree on Saturday, some pundits have claimed that conservatives are more likely to incite their partisans to violence. Historically, have American politicians on the left side of the spectrum suffered more attacks than their right-leaning colleagues?
Yes, but don't jump to any conclusions. Eleven U.S. presidents have been targeted for assassination, and eight of them—a clear majority—could be described as left-of-center. But that statistic is meaningless, because only Abraham Lincoln was killed by a right-winger with political motives. (Neither Lincoln nor his assassin, John Wilkes Booth, would likely have used the term right or left to describe their politics, but the labels seem fair in retrospect.) Some would-be assassins were motivated by personal revenge, like the delusional men who tried to kill James A. Garfield and Andrew Jackson (who's claimed by both the left and the right). Some were to the left of their left-leaning victims, like the anarchists who attacked William McKinley and Franklin Roosevelt. Others are hard to place on the political spectrum, like the Puerto Rican nationalists who tried to kill Harry Truman. Lee Harvey Oswald, a lifelong Marxist, murdered John F. Kennedy for reasons historians still scratch their heads over, and John Schrank, who shot Theodore Roosevelt, was crazy. * (He said he was angry not at T.R., per se, but at the fact that he was seeking a third term.) As for the right-leaning victims: Only Gerald Ford was attacked by a leftist assassin—the radical Sara Jane Moore. Nixon's and Reagan's would-be killers were both apolitical lunatics.
The picture is about the same in Congress and at the state level over the last century. Setting aside duelers, two senators and two House members have been assassinated while in office. Three of them were progressives, but only James Hinds of Arkansas was killed by a more conservative assassin for political reasons. Sen. Robert F. Kennedy was clearly on the left, but Sirhan Sirhan's motives are very hard to identify, as were those of Arthur Bremer, who tried to kill segregationist Gov. George Wallace in 1972.
There was a time in the United States when political violence was startlingly common and obviously one-sided. Following the Civil War, former Confederates used assassination to partially reverse the outcome of the Civil War. Twenty-four politicians were murdered in the South, most of them Republicans who were trying to enforce Reconstruction policies.
While assassinations are relatively common worldwide—a head of state has been assassinated two out of every three years (PDF) since 1950—no study has attempted to characterize the political leanings of the attackers and victims on the left-right political spectrum. However, dictators of all political stripes have cause for concern. They are 30 percent more likely to be assassinated than the leader of a democracy.
Got a question about today's news? Ask the Explainer.
Explainer thanks James W. Clarke, author of Defining Danger: American Assassins and the New Domestic Terrorists; Joanne Freeman of Yale University, author of a forthcoming book on political violence; and Benjamin Olken of MIT.
Correction, Jan. 12, 2011: This article originally misspelled John Schrank's last name. (Return to the corrected sentence.)