The importance of establishing the real size and kind of threat we are facing remains crucial for fighting it effectively -- hitting the right targets, picking the right means, avoiding overreactions. It is also important because the bigger and nastier the threat is (or is thought to be) the harsher are the infringements to civil liberties that can be justified and accepted by the public. One way to defend our liberties is to be alert to the forces that could exaggerate and distort the threat.
The difference between contemplating preemptive war and jumping at shadows can become perilously thin.
One would hope that the intelligence services can square the circle between over- and under-estimation, tell us what the real risks are, who are the enemies, and make the unknowns known. Yet there is growing evidence that even well-meaning spies can incur all sorts of troubles, especially under post-9/11 pressures. An increase in the demand for secret information creates an increase in supply, but the supply of inaccurate information grows faster than that of accurate information.
If we work on the principle that we do not know what we do not know, anything can look large enough to merit the intrusion of the authorities and the trampling of liberty.
We should of course distrust politicians who lie and exaggerate the facts to suit their agendas. But the questionable rationality of the post-9/11 mindset and of the strategic approach it has induced ... poses far more serious and consequential problems for all of us than propaganda or low-level conspiracies.