I think there’s a psychological factor that may be particular to Americans’ polarized method of thinking and sharing information. Many people here seem to think that a successfully prevented calamity is actually evidence that the calamity was “overhyped.” Recent examples: Y2K, post-9/11 security, H1N1, just off the top of my head.

It will take strong persuasion to get people to believe that a threat is real, and collective action is warranted. WWII was a long time ago, and we’re not wired for collective sacrifice anymore.