I can't say I know much about the history of Buddhism, but I think I know something about the practice itself. Christianity is a religion of action - a religion that speaks out and acts out. It's a religion that goes to war and asserts itself to gain followers and prove points. From what I understand about Buddhism, it is a 'passive' religion. It is a system of belief that stands on meditation and response rather than reaction. I haven't really heard of any Buddhist groups starting wars, fighting in battles, and singing in victory. Their triumph comes in quiet ways whereas it seems that Christianity triumphed in loud and obvious ways.