ASSASSINATIONS….In a comment responding to M.J. Rosenberg’s post about right-wing Israeli extremists who venerate Yitzhak Rabin’s assassin, Matt Yglesias says:

It’s hardly an original-to-me observation, but Amir really does seem like the rare assassin who actually managed to be quite effective at advancing his agenda.

I’ve heard that frequently myself, but is it true? John Wilkes Booth may not have saved the Confederacy, but in the longer term he was probably pretty effective — though I suppose you can always make the argument that things would eventually have turned out the same regardless of whether or not Lincoln had served out his second term. But that’s cheating: if you take that view of history, then assassins are ineffective by definition and the game is over before it begins.

Part of the problem is that too often we don’t even know assassins’ motivations in the first place. Lee Harvey Oswald and Sirhan Sirhan are ciphers. Ditto for James Earl Ray and Arthur Bremer, and Charles Guiteau had nothing more than a personal beef. Among famous American assassins, that leaves only Leon Czolgosz, who did have a motivation (justice for the working class) and pretty thoroughly failed to do anything about it.

[UPDATE: In comments, Will Divide points out that Teddy Roosevelt, though obviously no anarchist, was friendlier to business reform than McKinley. So Czolgosz may have done his cause some good after all.]

Gavrilo Princip? Serbia certainly didn’t do well in the aftermath of WWI, but then again, neither did Austria-Hungary. Brutus? That didn’t turn out as planned, did it? Ditto for Nikolai Rysakov et. al., though I suppose one might argue that in the long run they got what they wanted. Nathuram Godse? Hard to say. If his goal was eternal enmity between India and Pakistan, I suppose he got it. Christer Pettersson? Apparently there was no motivation at all.

So: who’s the most successful assassin in history? That is, the one who most effectively advanced his stated goals? Is it Yigal Amir, or does someone have a good case to make for someone else?

UPDATE: Henry Farrell alerts me to what the heavy hitters in the academy have to say about this. First, Jones and Olken:

Using a new data set of assassination attempts on all world leaders from 1875 to 2004….We find that, on average, successful assassinations of autocrats produce sustained moves toward democracy. We also find that assassinations affect the intensity of small-scale conflicts.

Second, Iqbal and Zorn:

[A]n analysis of all assassinations of heads of state between 1952 and 1997….Our findings support the existence of an interactive relationship among assassination, leadership succession, and political turmoil: in particular, we find that assassinations’ effects on political instability are greatest in systems in which the process of leadership succession is informal and unregulated.

So there you have it.