The United States has a pronounced lead over all other countries, but its potential success may encourage others to follow suit, setting up a new kind of arms race; it may also lead to opponents developing new ways of retaliating. In the light of the attacks of 11 September, this is not to be discounted. What a stinking load of unprocessed sewage. The 9/11 attacks didn't take place because we had developed weapons that worked too well. So now because of the 9/11 attacks, we're supposed to hamstring ourselves, for fear that if we gain an unfair advantage, it will make somebody mad enough to hurt us?
I think their point is that lasars and other sophisticated technology won't stop unanticipated unconventional terrorist attacks.