Strick:

No, I didn't say that everyone in the family is guilty by association. I just said it was patently absurd to say that the family was not linked to terrorism. The most notorious terrorist in the world is a member of the family. That is a link. It is a link that deserves close investigation, and it did not receive close investigation. This was clearly one of Moore's points in the movie.

Secondly, the film presents evidence that Osama was NOT in fact completely estranged from the family, as the usual media echo-chamber tells us. He has had infrequent but friendly contact with several family members since becoming the most wanted terrorist in the world. Therefore there is good reason to suspect the family might know something useful.