If you will recall, there was a "culture of avoidance" in the FBI that was pervasive at the time, reinforced by the, as it turned out misguided, emphasis on "heightening the wall" between the domestic & foreign intelligence agencies even more than the law strictly required (Gorelick doctrine). The mindset was such that there was almost no incentive to aggressive prying for fear of private or public reprimand for having overstepped murky bounds, particularly when potentially stepping onto the CIA's turf. After Ruby Ridge & Waco, one can understand, if not condone, the timidity of the FBI in these areas. I don't excuse them, but agencies of our own government were operating at cross purposes to a great extent at the time. To the extent the judge denied a request to access Moussaoui's laptop on the basis of one or more technicalities when common sense warranted access, the FISA process was also part of the problem.
Cheers,
Daiwa