I sincerely doubt you've got any scenarios that haven't been concieved of and/or discussed openly elsewhere. Security against terrorists is a lot like security online: it's easier to devise defenses against threats which are known (or realize which are not readily defended against) than to fight unknown bugaboos.

I'd not fret about speaking out.

One early conversation I had on this matter was that there are some structural similarities between terrorism and the free software movement: large numbers of largely independent cells. Actually, my comment was "now you know how Microsoft's felt -- trying to figure out where to strike agains the free software movement". There are also some key differences: for the most part, free software folk are white hats -- there's nothing inherently illegal (DMCA and SSSCA excepted) with what we're doing. We can communicate openly. The black hats can't. We should use our open communications channels as an advantage: we can cover more ground, more flexibly, than the black hats. Secrecy is ultimately, in many caces, a hinderance, not a help. Exception: specific, time-sensitive data.