Also, there's the internet. I think we're only starting to discover how that changes the dynamics.This comment by "Canadian Reader" is welcome and substantially true. The only thing to add, though, is that the Internet's structure (especially the blog medium) does tend towards reinforcement of majority sentiments, and despite the resurgence of the left online over the last six months or so, it's still primarily right-wing.
A "dissent is treason" chant is powerful, but it doesn't work fast enough. At the beginning, everyone reacts to it with horror and revulsion. To take effect, it depends very much on making individuals feel helpless and alone. What's different this time is, ordinary people are able to talk to each other and find out that they are not alone in their dismay.
Moreover, war-mongers no longer control what people can know, if they want to find out. There are blogs, there's google news, there's the world press, there are web sites to coordinate protests...
There's hope. Maybe not to stop the war. But to stop the resurgence of McCarthyism, yes. You can do it.
(As for how long, though... the internet-savvy children teenagers that we're seeing all over are going to dominate over the old-school libertarians; it won't eliminate the right because teenagers can belong to any number of political ideologies, but the sheer numbers will make the current imbalance somewhat irrelevant.)
Now that the allure of e-commerce is over, the Internet has returned to its original and (in my opinion) best suited role: as a mass-to-mass communications medium. CR above has noted one of the repercussions, and it's welcome. Unless, of course, the powers that be decide to "do something about it".