YANBU to see students out protesting and making a stand. About bloody time the politicians had angry faces to worry about. It's part of the political process, much as the police often treat peaceful protesters like criminals (personal experience). YWBU to delight in seeing people get hurt, but I'm sure that's not what you meant.
Absolute bollocks btw whoever posted that protests always have an element of violence to them. I have been on quite a few protests and the only behaviour from protesters I have ever seen that the police classed as "violent" was the person who tried to grab the Olympic flame in London, which is IMO a stretch of the idea of violence (don't snatch darling). OTOH I have seen the police drag people, carry them, push, shove, pin down etc.
Sophable - there were loads of young people and students protesting about the war. I held a protest at school, with quite a lot of others, as did lots of people up and down the country. And then marched in London where I saw loads of people a similar age to me (teenage).
UQD - aren't you the cool one to have totally forgotten your passion for politics and strong belief in protesting things you think are wrong. Good for you. Don't tar all these strong minded young people with the same brush though there's a dear.