Does protesting in the streets ever work?

Does doing mass protest ever work?

On local issues I can see it working. Ie protesting against your local council or your workplace.

But on huge issue like war. Vietnam war you have demostrations after demonstations. Did that stop the war? The US only stopped when they lost the war. The iraq war protest didn't stop the war. In UK the mass protest against the ban on fox hunting didnt change anything.

Live 8 is a mass demostration by itself against the G8 summit. Does it do anything?

I live in Myanmar where every fucking person can tell you about someone they lost in 1988 protests.

The moral: Mass protests in a democracy are annoying. Mass protests under a dictatorship are blood baths.

Oh yeah, and partying to help starving people is retarded