It's just “preliminary†evidence. Could be that Tamerlan, when he wasn't busy favoriting Chechen jihadist videos on YouTube, was building up an explosive hatred of marathons.This AP story is actually newsy, not because of the conclusion officials have drawn but because of how they drew it: Two U.S. officials say preliminary evidence from an interrogation suggests the suspects in the Boston Marathon attack were motivated by religion but were apparently not tied to any Islamic terrorist groups.The two ethnic Chechen brothers practiced Islam.The U.S. officials spoke Monday on condition of anonymity because they were not authorized to publicly discuss the...