Usual response.
Expressing ANY opinion isn't, of course.
However, not to be too obvious about it, expressing an opinion that is anti-American and anti-Western IS anti-American and anti-Western. I saw the signs and heard the speeches, and I know what they were talking about.
It wasn't anti-war. If it had been just war, there would have been at least a few signs and speeches about Saddam.
When I write something, it has an exact meaning. The motivations of many of those who organized the antiwar protests was not to stop the war, but to stop America. Exactly the same people have generated mobs for many other "causes," most recently world economic issues, but the basic motivation of opposition to America and the West is still the same.