If people are jumpy and fearful, terrorists have done their job.
Make people afraid to get on a bus or a train, afraid to travel or afraid to go to a concert or a ballgame, and terrorists have done their job.
Make people willing to give up their personal freedoms in the hope of a fleeting sense of security, and terrorists have done their job.
Make people look with suspicion at someone who appears different, and terrorists have done their job.
The recent bombings in London illustrate the futility of turning a city into a fortress. No city in Europe has had more experience in dealing with terrorism than London -- experience gained during the Irish Republican Army 's bombing campaign in the 1970s and 1980s.
There are thousands of video cameras in London. There are numerous concrete barriers and police checkpoints. The city has a visible and active police presence. And yet in the space of two weeks, two coordinated attacks occurred in London.
National ID cards, hidden video cameras, increased surveillance, random searches and the rest of the trappings that come with transforming an open society into a garrison state will not stop terrorism.
What will? Two things.
First, the United States must begin acting in good faith at home and abroad to reduce the grievances that inspire and feed terrorism.
And second, we must steadfastly refuse to let anyone, be they terrorists or the people who say they will protect us from terrorism, scare us into leading fearful, shrunken lives.
When our government stops supporting dictatorships, stops exploiting other nations for oil and other resources and stops trying to change the world at gunpoint, that is when the swamp of revenge and resentment is drained and hatred no longer can fester and grow virulent.
When we can travel freely without being subjected to searches and security measures that are long on show and short on effectiveness, that 's when terrorism will lose its sting. A proud, unafraid people will never be intimidated by those who wish to sow fear in order to destroy us.
This is not to downplay the threat of Islamist terrorism. It is real and perhaps the greatest security challenge that the western world has had to face. And terrorism is effective because it attacks the weaknesses of human nature -- our aversion to risk, our lack of rational thinking in times of crisis, our reflexive anger.
This won 't be easy to counter. Terrorism strikes at the very core of modern society -- our ability to function with confidence in our daily environment.
Fear is the terrorist 's ultimate weapon. It is up to all of us to reject fear, anger and revenge and not let them, or our government, scare us into destroying all we hold dear.