I used to post political issues, mostly uncontroversial stuff (ex. rape bad), but I came to find out that several of my friends, turned out to be extreme conservatives. If you had a conversation with them about anything non-political, you never would have guessed in a million years (hell, one of them's gay, even). I've had some unfortunate experiences where I lost two friends who I've known for like 12 years cause of politics so I try to be careful about that shit nowadays.