[T]he war against terrorism has not yet been much of a war at all, let alone a war to end all wars. It is a messy, difficult, long-term struggle against exceptionally dangerous criminals who actually like nothing better than being put on the same level of historical importance as Hitler--can you imagine a better recruiting tool? To fight them effectively, we need coolness, resolve and stamina. But we also need to overcome long habit and remind ourselves that not every enemy is in fact a threat to our existence.
But Bell's point is broader: All societies, not just our own, tend to overstate the dangers they face. If this weren't the case, after all, it would be harder to motivate people to fight and die. (Cass Sunstein raised some pragmatic objections to this line of thought in a recent review for the magazine).
Terrorism is certainly a serious danger, and if Islamic fundamentalists can get their hands on a nuclear weapon, perhaps we would be in existential danger. But it's worth remembering that even the Sandinistas were billed as a threat to our way of life, and we have a (sometimes understandable) tendency to overstate our own peril.