Here’s my short reply to Why Protest? (from my comment on Christy’s blog)
We protest for two reasons: to stay true to our convictions by speaking them and to allow others to notice those values/convictions and possibly be compelled by them.

1. Think of it like getting baptized, and outward expression of an inward commitment. Sometimes we need to protest not to change the world, but to keep the world from changing us. You can’t be neutral on a moving train, unless you are actively voicing your conscience, you are often passively agreeing with the majority.

2. Regardless of how unlikely it seems, people do hear/see/notice you and other protesters. They’re response might not always be what you would like for it to be, but they do take note.
Politicians take note of what the people think, polls, phone calls, letters, protest, etc. They might listen more to lobbyist, but they keep a careful eye on what the people think. I think it’s a credit to the many individual protesters who went out into the streets in the early years of the Iraq war that the general public was open to the idea of questioning the administration and war tactics. Protesting is simply taking a strong stance on something you believe strongly in and hope to compel others to believe in also.

The truth is we protest all the time, it just takes different forms. We rant on our blogs, we critique in conversation, we choose not to shop certain places, we complain to customer service (apple maybe?), we march, call, write letters, lobby, we protest. It is not unusual, though in many ways it has become rather unoriginal.