Not to invoke the label of "conspiracy theorist", but I have to think that if those in power really wanted the threat to be gone, we have all the means and methods necessary to effect such desire into a reality in fairly short order. I don't think the establishment is as interested in making the world a safer place to live as it is to maintain a venue whereby they can justify certain activities for "the ever diligent and greater good" of our society.
I just can't accept, given what I know about our own capabilities, that we really are unable to neutralize any threat swiftly and completely if we really wanted to. If there was a real will to stop the terrorists, or the invasion of America, or the proliferation of nuclear arms, then it would happen and happen rather quickly.
It makes much more sense that we maintain this "threat level" as justification for ongoing funding of certain programs, generalized increased scrutiny of the masses, and securing ever increasing levels of tyranny. Who 10 years ago would ever have thought we would be standing in security lines for hours just to go from Seattle to Portland, and not be allowed to bring a book of matches or a bottle of water with you? Yet they can't(won't) stop anyone from just walking into this country as they please?
We are moving towards PHRASECENSOREDPOSTERSHOULDKNOWBETTER. in leaps and bounds these days. I never thought being a citizen would be such a debtriment in my lifetime.
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The ultimate result of shielding men from the effects of folly is to fill the world with fools.
-- Herbert Spencer, English Philosopher (1820-1903)