The ultimate sophistication of subversion is to take over the government, not by unlawful but by lawful means.
A society that does not defend itself is doomed. A system that remains passive in the face of attack deserves to go under. Those unwilling to defend freedom will become unfree. To stand idly by is to commit suicide.
I've never been to the Soviet Union and the main reason for that is I was warned several times by people from the KGB who had defected to the West that it would be very unsafe for me to go there
I've tried to make a book that's accessible to the ordinary, intelligent reader. Very often books that cover this kind of subject are written by academics, for academics. But I am not an academic.