It is odd to me that dad asserted he thought of his son as a good boy; it implies that others might think he was not. In other words, father has been told by authorities that his son might have been involved with terrorists and they are investigating (how do you tell a father that his son blew himself up using a suicide vest and not ask father whether son was involved with Muslim terrorists?). If the son had committed suicide in a more traditional way, the father wouldn't need to defend his son's goodness, IMO.
Now that you bring it up, everything the father said can be taken as a confirmation that he was told his son was a terrorist. "thought he was going to have a good life," "good boy," etc. Learning your kid is about to become a devil 160,000,000 Americans sure would make you distant and shocked, and only capable of small complements. Great insight.
I am taking it the same way. The kid decided to go in his own apartment and move out of the fraternity this fall. Now he has all the bomb making supplies and they have detonated something that I heard 4-5 miles away and I am expected to believe that this is just a depressed kid? No way.