[Designer]

"The equivalent in the US would be if the Democrat or Republican parties had their own private armed forces."

I think we have seen cases where the Dems have used strong-arm tactics (THUGS & VANDALS) to enforce, coerce, frighten, and punish their ideological enemies, but I don't think Republicans have, or ever would, thank God.

[Restorer]

But in even the most extreme cases in the US, I'm unaware of political parties forming their own armed, uniformed paramilitary groups.

Perhaps the closest equivalent was the KKK in the early 20s, when they controled a good dozen state legislatures. Although I'm not sure you can call a sheet a uniform. :)