The Washington Post has a primer on the ETA, the Basque separatist group that is widely believed responsible for the horrific train bombing in Spain. I've seen varying numbers of casualties, from 182 to 190. I also heard minutes ago on BBCs The World, some rumblings about possible Al Qaeda responsibility for the attack.
At any rate, this primer is a good resource if one doesn't know much about Basques or the ETA. This was an unforgivable act of terrorism, no matter who is responsible. But I must tell you that I used to have a Basque friend. Her stories about the persecution that her family had suffered were also unforgivable. She had a drawing in her house of a warrior on a horse. It was actually a coded message that her father had sent to his family after they were able to flee to America, telling them that he was still alive. Teresa was one of the most wonderful, vital women I've ever met. I've lost contact with her - she went back to Spain, the last I heard. I hope she is alright, because that's the problem, isn't it? A terrorist doesn't know who is likely to die when he or she attacks civilians.
That said, the primer should make it clear - the Basques have been fighting for their existence for as long as the Celtic Irish, to whom they are thought to be linguistically related (as well as the Georgians of Russia) have been. It doesn't make this right, but perhaps someone should start listening.