Beastie Boys had one of the first and best of the anti-Iraq-War songs, I can't think offhand of one that was more "mainstream" at the time and still explicit and specific about it.

Well I'll be sleeping on your speeches 'til I start to snore
Cause I won't carry guns for an oil war
As-Salamu alaikum, wa alaikum as-salam
Peace to the Middle East peace to Islam

And so on. It might not have been the best (IMO that is "Empire" by Dar Williams, with haunting sadness, historical scope, and irony), but it was big.