I'll say a little of all the above.
I this type of protests, like in the anti-global ones there are many components, and is too easy to generalize.
A generalization can satisfy a professional hater like Grun or Hort, but not someone that ask himself questions.
So, there are "anti-war", "anti-this-war", "anti-bush", "anti-USA", anti-anything", "let's-have-fun", "I-dont-know-why-but-i-protest", and so on...

In Rome they amounted 3 million people. Almost.
A big number, anyway... a record afaik.
They are all dumb idjots commi gay studmuffingot sobs??
I dont know, I dont know them personally.
But they disagree, and have the right to express it, and maybe this was the only way they had to do it, since the media (all of them in Berlusconi's hands) here are ALL pro-war.