The first is a valid reason, of course, and doesn't bother me, even though I am concerned with secret government dealings.

But they consider with many other issues besides national security in their deliberations about foreign investment in the U.S..

Perhaps only the part of their discussions dealing with security issues should or could be conducted secretly.

As far as your second possibility goes, of course that may not be the case.

But would you be surprised or shocked to learn that it was?

I know I wouldn't.