"Take a look. The enemy...how long has it been since you've seen him? I mean really seen him? Take a good look. Well, what do you think? Do I look like somebody who wants to blow up the world? She thinks I do. Dammit, stop thinking that all Americans are goons and idiots. They are probably as many people in my country that don't want those weapons lying around as there are in yours--maybe more. I'm not saying they're right. Maybe those weapons are keeping the peace exactly as they say they are. But there's one thing I do know. You're wrong. You're wrong when you lump together every damn thing you don't like and call it American. If you know me and don't like me, fair enough. But if you don't know me and don't like, that's just damn foolishness."
--Carl Hostrup (Reunion at Fairborough)
What is the real driver behind political demonstrations? By publicly amassing in large numbers to march, wave signs, and chant, protesters might think that if they scream loud enough, then they will turn people toward their view.
This seems naive. Just as likely if not more so is that people will be turned off by what can be seen as juvenile behavior--i.e., people kicking and screaming like little kids because something is occurring that they don't like. As such, demonstrating political opinion in public view might reduce support for that viewpoint.
More plausible, it seems, is the notion that demonstrations make protesters feel good about themselves. Similar to high school pep rallies, demonstrations promote mutual assurance among the protesters that there is strength and solidarity in numbers. Mix in some civil disobedience from occasional arrests for, say, disorderly conduct and you get a mechanism for self-validating rebellion.
Which brings us to another possible motivation for political demonstration: to spark unrest. Demonstrating, for example, in the midst of someone else's political rally is like a spark in search of tinder. The idea is to incite violence, and somehow turn the narrative to implicate the other side.
By taking on the appearance of victims rather than of instigators, demonstrators hope to indirectly attract support for one's position by winning the sympathy of onlookers.