During the lifetime of this Parliament, Tony Blair will have to decide whether to let the United States use two bases in Yorkshire as part of President Bush's controversial plan for a National Missile Defence system (NMD) or Star Wars, as it has become known.
The development of Star Wars is likely to make the world a more dangerous place. Any attempt by the US to build a missile shield is expected to spur countries such as China into an arms race to try to overcome the shield, and to jeopardise nuclear arms control agreements with Russia.