Certainly a valid question.
Lyrics are fine as long as they're not being posted in a effort to slide politics in, "under the radar" and the best way to proceed if one wanted to post lyrics is what I used to tell my kitchen staff; when in doubt, throw it out. If you think it has the possibility of being perceived as political or think it could potentially spark debate, throw the idea away.
The shitty part is that you never know when someone is going to fly off the handle. The first perma-ban for politics here was because someone thought a joke completely unrelated to politics was a political jab and he wrote a "I'm telling the whole world what I think of everyone and everything" diatribe that if any employer saw would have caused a termination of employment, never mind a ban from a forum. And that was after repeated warnings.
Bro, have you heard the first few Lamb Of God albums? Rage Against The Machine?