The lone wolf terrorist

So after somewhat recovering from the wounds the surviving suspected terrorist has started talking about who was behind this atrocity. And the picture that is becoming clearer every day is that the suspect's elder brother became radicalized while he was in Russia. But another story states that he was radicalized here. No matter where he was radicalized, the point is that he was a lone wolf who was inspired by some radical material on the internet and contacts with some shady people. It was initially suspected that Al-Qaeda or the Taliban in Pakistan had to do something with it but before the connection was established, the Taliban said that they did not have anything to do with the bombing. With emotions running very high, no terrorist organization wants to have the military might of the U.S. on them suddenly. When days went by, I suspected to realize that it must be just these brothers who did it on their own and not some terrorists organization (for reasons elaborated above) because these organizations if they have done something spectacular would claim responsibility right away to boost morale of their people and gain new recruits from disgruntled people. And now it has been confirmed (although the investigation is ongoing) that it was only these brothers who went crazy and did this horrible act against their adopted country. What was the motive behind the bombings will be clearer in coming weeks or we may never know what motivated them to do it.