3. Dave Mustaine
Any fool knows that if you perform in a politically volatile area where there has been violence, you keep your mouth shut and pray to (insert applicable deity here) that you make it out of that area with your kneecaps intact. But thrash metal band Megadeth's frontman Dave Mustaine was naive in that respect and accidentally sparked a riot by unknowingly supporting terrorism. While playing a gig in Northern Ireland during the Troubles, Mustaine dedicated a song to what had been described to him as the cause, unaware that that specific term was a euphemism for the IRA. The audience didnt respond well to what they perceived to be Mustaine publicly supporting the IRA and fighting between audience members broke out. Mustaine later said of the incident I never felt so stupid and has presumably learnt to not publicly vocalise opinions on politics. Particularly ones hes unfamiliar with.