I happen to be old enough to remember when the stakes in the nuclear stalemate was the survival of the entire planet. It almost seemed like we were given a puzzle. "Can the human race figure out a way to get along without anhilating the entire planet." Facing such choices we nevertheless (except for a few zits -J Edgar Hoover, Nixon - Kissinger) chose to keep the Constitution of the United States intact and if we did engage in horribly unethical behavior (blind LSD trials, sensory deprivation research) we at least had the decency to PRETEND we weren't doing it. Besides we had a monolithic scary enemy to point to to justify the actions.
Fast forward to 2006:
We are now so afraid of 15 guys armed with box-cutters, that we're completely trashing the Constitutional protections that have served us so well these last 200 years and were openly declaring our willingness to use the same techniques which justified our outrage in years past. In other words we are becomming our enemy.