At Newsweek, Daniel Klaidman describes fearmongering as a political strategy:

Americans are historically a tough lot. But the policies and rhetoric of the Bush-Cheney years, which set the tone for the current GOP attacks, are infantilizing: be very afraid, we’re told, and let the government take care of you. The tough-guy bluster has led to a permanent state of anxiety—and a slew of counterproductive policies, from harsh visa restrictions to waterboarding. Our politicians rail about apocalyptic threats while TSA officers pat down toddlers at the airport. The irony is that many potentially lethal terror attacks—from United Flight 93 to Richard Reid to the underwear bomber—have been foiled by regular citizens.

Echoes of this.