This bit over at Crooks & Liars is illustrative:

Have you noticed how many right-wingers are decrying the “tyranny” of the Obama administration these days?

It’s particularly rife on the Tea Partying far right, where it’s extremely common to hear Obama being portrayed as a “tyrant,” particularly regarding his recent attempts to promote gun-control measures.

[…]

I was reminded the other day, rereading Stephen Budiansky’s marvelous book about Reconstruction, The Bloody Shirt: Terror After the Civil War, just where the right-wing fetish about “tyranny” comes from. It’s a highly selective fetish, after all; none of these “libertarians” seemed even remotely concerned when George W. Bush launched the whole “enemy combatants” enterprise back in 2001.

According to Budiansky, it — like the phrase “waving the bloody shirt,” as well as the whole conservative adoption of that rhetorical ruse as an aggressive form of defense — has its origins in the years during and immediately following the Civil War, when it was common for Southerners to sneer at Abraham Lincoln (alive or dead) as a “tyrant”:

Budlansky’s book includes this:

A bald fact: Generations would hear how the South suffered “tyranny” under Reconstruction. Conveniently forgotten was the way that word was universally defined by white Southerners at the time: as a synonym for letting black men vote at all. A “remonstrance” issued by South Carolina’s Democratic Central Committee in 1868, personally signed by the leading native white political figures of the state, declared that there was no greater outrage, no greater despotism, than the provision for universal male suffrage just enacted in the state’s new constitution.

Huh. Pure coincidence, I’m sure.