In the course of its history, it developed many different manifestations in different places, and is continuing to do so today. Unlike Christianity in the period up to the Reformation, there has never been a single "authoritative" source of doctrine and organizational control for the whole movement. Thus, it is not at all surprising that one can find many contradictory phenomena in that history, including some that were quite violent, and some which were (by our contemporary Western standards) very feudalistic. Because of the background of Christianity in Western culture, we tend to assume that a religion must have some sort of "orthodox" dogma, but actually Christianity is the exception among world religions in this respect.
My own interest in the subject has concentrated on the Zen variety, rather than the Tibetan. Of course, the role of much of the Japanese Zen community in giving ideological and spiritual support to the Japanese militarists in WW II is well known, but that doesn't mean that American and European Zen students today would agree with the supporters of the old Japanese armed forces -- far from it! While not one of his followers, I think the Dalai Lama has a lot of valuable things to say about Buddhist doctrine in particular, but his political opinions, on the other hand, are often far from mine (such as his opposition to abortion and homosexuality). But you have to remember that he grew up and was educated in a very different cultural milieux from ours. Lots of left-wing Catholics also consider the Pope to be their spiritual leader while strongly disagreeing with him on abortion, etc.
Naturally, people who are opposed to all religions in principle will also sneer at Buddhists and Buddhist ideas, such as rebirth (Buddhists don't use the term "reincarnation"), but they should keep in mind that a lot of Western Buddhists don't really consider Buddhism a religion at all, at least to the extent that Judaism, Christianity, and Islam are paradigms for religion to most Westerners. Rebirth, for example, is not at all a dogma in the Christian sense -- many Western Buddhists don't accept it at all, or at least are basically skeptical on the subject. They consider it as a set of teachings by a very wise teacher (not a "son of God" or "Prophet" or anything like that -- just a human being) about how to live, the value of which needs to be decided on by everyone in their own lives, like any other teacher's utterances. Politically, Western Buddhists run the gamut from left to right to apolitical, but the distribution is probably skewed strongly to the left, as far as I can tell.
Basically, I would just like to point out that Buddhism is a much more complex subject than most of the posters in this thread up to now seem to realize.
Jon Johanning // jjohanning at igc.org __________________________________ After the Buddha died, people still kept pointing to his shadow in a cave for centuries—an enormous, dreadful shadow. God is dead: but the way people are, there may be, for millennia, caves in which his shadow is still pointed to. — And we — we must still overcome his shadow! —Friedrich Nietzsche