For many, the dream of a shield that would protect a country from ballistic missiles is just that — a dream or fantasy. Any state possessing more than a rudimentary arsenal would be able to defeat a missile defense program, either by overwhelming it with the sheer number of missiles or by confusing it with decoys or other countermeasures. Indeed, some skeptics claim that such a project is unworkable in its entirety and a colossal waste of money.

Governments on the other side of that shield — those looking in — have a different view. For them, the prospect of a functioning missile defense program is troubling, as it heralds the potential nullification of weapons systems they have invested billions of dollars in and which constitute an irreducible minimum level of defense. They rely on ballistic missiles to deliver the nuclear warheads that deter enemies from blackmailing or attacking them.

It is difficult to tell how seriously Russia truly fears the U.S. missile defense program. Moscow loudly objects to Washington's plans to deploy interceptors in Europe, a deployment that is intended to counter the threat posed by Iranian missiles.