21.   The two sides have been trying to build on a commitment by Presidents Clinton and Vladimir Putin to improve safeguards against the accidental launch of nuclear missiles.

22.   There is a threat of an accidental launch of a missile.

23.   While Chinese missiles could easily be retargeted in the event of hostilities, the agreement would make less likely any sort of accidental launch toward the United States.

24.   Republican leaders argue that the ABM treaty is outmoded and that the United States needs a defensive system against an accidental launch by Russia or some other nuclear power.