I am not an Amazon supporter but come on, do you think if you were hosted on any other US service, rackspace or what have you, that they would keep hosting you while the us govt was pressuring them to shut you down?
Dreamhost has a reputation for being pro-free-speech, and there are some anecdotes online that support this. Their TOS are also on the more friendly side, from what I've seen. I've also been quite pleased with their hosting in every other respect.