/pol/'s sanity has very rapidly declined over the past few years (granted, it wasn't very stable to begin with).
Around 2012, it was mostly just libertarian circlejerking, then somewhere between 2013-2015 it turned into a neoconservative, christian forum that was determined to undermine the quality of neighboring boards. Then we got to the election and it became straight-up far right nationalism. Skip ahead a little bit then you got to white supremacy, nazism, and other what-have-you extremely far right beliefs.
Post-inauguration is the latest decline, with /pol/ now being a literal Infowars watching, climate change-denying, anarchist wasteland of socially-stunted teenagers.
It's like a never ending pit. Just when you think it can't get any deeper, it does. Personally, I predict the next big /pol/ thing will be evolution-denying/flat earthers.