Why Demonstrate?

I'm old now, and I've spent my share of time demonstrating against needless wars and working in a pragmatic way to help elect office holders who support minority voting rights, women's rights, gay rights, etc. I worked on issues because I was hopeful. I understand that our system barely qualifies, in any sense, as a democracy. I know that social scientists have shown that our citizens have lost much of their chance for upward mobility (downward social climbing remains an option). But I have witnessed progress in certain areas, so I continue to do what I can. 

There are people in my peace group who regard the United States as the fount of all evil. I was talking with some of them last night, and this morning I woke up wondering why they take part in demonstrations. They believe that the country is irremediably corrupt from head to foot. Except for the 2% of the voters who agree with them, every political motive is evil and every President is Satanic. If I believed that, I'd spend my days reading philosophy, watching Masterpiece Theater on TV, drinking bourbon and smoking joints, enjoying my family and good friends. I'd let the world pass by. There would be no point in protesting or working for causes. I might take up one of the passive forms of Buddhism. Yes, that's the ticket.