There is no reliable defense to ICBMs.
 EffectivenessMany still consider missile defense to be destabilizing. French policy makers consider that the 1972 Anti-Ballistic Missile (ABM) Treaty and the doctrine of Mutual assured destruction to be the cornerstones of strategic stability. Some French analysts viewed missile defense as jeopardizing both the doctrine and the Treaty, as well as risking a new arms race.
Experts however question the precision of the system. All the experiments to develop and test MDS were scripted so far and nobody knows about their credibility in an actual war situation. Knowing the speed of these missiles, it's more difficult than hitting one bullet with another.
Moreover, most French security experts doubted the technological feasibility of ballistic missile defense. Some think it is foolish to spend huge amounts of money on unproven technologies that lacked operational or political usefulness. Instead, the French defense policy community viewed missile defense merely as an American "economic weapon" used to defeat the Soviet Union and win the Cold War.
Some are simply of the opinion that reliance on missile defense as an element of nuclear deterrence is wrong and that missile defense is a bust technically, and it encourages the proliferation of both nuclear and conventional weaponry instead of preventing such an increase from taking place.
Critics of Missile defense also state that just as with nuclear weapons, the U.S. infatuation with missile defense will cause other nations to desire this expensive and destabilizing technology.
Russia's top military officer has threatened to carry out a pre-emptive strike on U.S.-led NATO missile defense facilities in Eastern Europe if Washington goes ahead with its controversial plan to build a missile shield. Russian Defense Minister Anatoly Serdyukov also warned that talks between Moscow and Washington on the topic are "close to a dead end." U.S. State Department special envoy Ellen Tauscher responded that neither country can afford another arms race.