I can only contrast the reactions to the 9/11 US bombs with the 7/7 London ones.
After 9/11 the US media stirred up a sky-is-falling frenzy that frightened half the US into hiding under it's bed. I flew to/from the US several times soon after that, the planes were empty. 50 passengers in a 747 economy cabin, we all had flat beds to lie on :)
I was in the US when 7/7 happened, and saw the incredulous reaction of the US media when they discovered that Londoners were back on the buses and underground on 7/8. The idea of "we can't let them win" seemed to amaze journalists who expected London to be deserted as terrified people stayed at home.
As anyone who lived in N. Ireland in the 70's and 80's will tell you, you'll never stop every determined terrorist from getting through, but if you let the ones who succeed determine your actions, they have won and we have lost. Statistically speaking you're still far more likely to be killed in a road accident, but do we leave our cars in the garage? No, we fit airbags, use seatbelts, and know that the chances of us not coming home are really quite small.
It takes some courage, yes, but so do most worthwhile things in life. It was what drove the pioneer spirit of the first european settlers in the US, and it's sad that their descendants have lost it. What is even more of a problem is that so many of the world's leaders have also lost it. I hate to think what Churchill and Roosevelt would make of the reactions of Brown, Obama, et al. The heightened security, virtual strip search and general inconvenience plays straight into the terorists' hands. They've conned the authorities into doing what they can't do themselves, and the poor dupes in power either can't see it, or are too nervous for their jobs to admit it.
Forget the in-your-face techy toys, they're not the magic solution. The only security that works is the behind-the-scenes stuff that we don't see. Decent intelligence gathering by security services, and the courage of ordinary people not to let the bombers succeed, is the only way for us to overcome this. No potential semtex fart is going to keep me off a plane.