As usual Bruce Schneier articulates the straight scoop on security issues well.  In this article he also takes a swipe at the politicians with the “make people feel good” mindset.  From Wired News:

Sometimes it seems like the people in charge of homeland security spend too much time watching action movies. They defend against specific movie plots instead of against the broad threats of terrorism.

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The problem with movie plot security is that it only works if we guess right. If we spend billions defending our subways, and the terrorists bomb a bus, we’ve wasted our money. To be sure, defending the subways makes commuting safer. But focusing on subways also has the effect of shifting attacks toward less-defended targets, and the result is that we’re no safer overall.

Terrorists don’t care if they blow up subways, buses, stadiums, theaters, restaurants, nightclubs, schools, churches, crowded markets or busy intersections. Reasonable arguments can be made that some targets are more attractive than others: airplanes because a small bomb can result in the death of everyone aboard, monuments because of their national significance, national events because of television coverage, and transportation because most people commute daily. But the United States is a big country; we can’t defend everything.

One problem is that our nation’s leaders are giving us what we want. Party affiliation notwithstanding, appearing tough on terrorism is important. Voting for missile defense makes for better campaigning than increasing intelligence funding. Elected officials want to do something visible, even if it turns out to be ineffective.