I also often am given the chance to look through the varied venomous posts that have drawn their own lines in the sand. Usually, I realize that I do not want to add the growing partisan bickering, especially since I usually understand (even if I don't agree with) both sides. Putting my unsolicited opinion on these matters out into the world usually invites challenge, not better communication.
That's not to say that I don't have strong opinions on the issues of the day, because my views are quite strong. Nor does it mean that I won't make politically controversial posts from time to time (sometimes, I just can't help myself). Rather, the tiredness I feel right now makes the effort to reward ratio quite clear.
That, and it saves the world from most of my diatribes.