The truth is that even contemporary machines don't emulate speech very well, not even our own let alone dolphins' (in the conceit of this novel).
There'll be more later about the rather curious role of national intelligence in our lives. I've remarked on the catch-all of "national security" in another novel, and how it's used so freely to excuse so many misdeeds and so much foolery. Our safety has become no more than a political football.