BOSTON -- Tamerlan Tsarnaev ranted at a neighbor about Islam and the United States. His younger brother, Dzhokhar, relished debating people on religion, "then crushing their beliefs with facts."The older brother sought individual glory in the boxing ring, while the younger excelled as part of a team. Tamerlan "swaggered" through the family home like a "man-of-the-house type," one visitor recalls, while Dzhokhar seemed "very respectful and very obedient" to his mother.The brothers, now forever linked in the Boston Marathon bombing tragedy, in some ways seemed as different as siblings could be. But whatever drove them to allegedly set off two pressure-cooker bombs, their uncle is certain Dzhokhar was not the one pulling the strings."He's not been understanding anything. He's a 19-year-old boy," Ruslan Tsarni said of his brother's youngest child, who is clinging to life in a Boston hospital after a gunbattle with police. "He's been absolutely wasted by his older brother. I mean, he used him. He used him for whatever he's done. For what we see they've done. OK?"