The Coalition to Protect Americans Now last summer proclaimed on its Web site that, "Ship-launched missiles may be deployed by any country able to acquire the technology. Therefore, any country in the world is a potential threat."
From the other side, Theresa Hitchens, research director of the British American Security Information Council, said on July 6, "The post-Cold War world will get a lot colder if the Clinton administration freezes out NATO allies, Russia and China, and strides toward a missile defense decision."
In some ways, the basic arguments about whether such a system makes sense or not go back to the debate over the Strategic Defense Initiative (SDI), or "Star Wars" program, envisioned by former President Reagan.
In fact, the pro-national missile defense (NMD) Claremont Foundation claims that a recent poll shows 74 percent of Americans believe the U.S. already has a missile shield like the one Reagan proposed in 1983.
But today's debate is also framed by the differing ideas of what the reality of post-Cold War life is.
Those who support NMD paint a picture of a world full of threats, one in which the collapse of the Soviet Union has increased the risks of nuclear proliferation.
The High Frontier organization, for one, argues that "at stake is U.S. ability to project power and protect our strategic interests around the world. Effective defenses are needed to counter these growing threats" such as Iran, Iraq, Libya and North Korea.
Many critics believe the technology is not feasible and that the Pentagon's testing methods are fatally flawed. Some say the system's backers have overstated the threat of rogue missile launches.
Other critics say that even if it worked the weapon would not be worth the international outcry against it most notably Russia's threat to unravel other arms control treaties.
Both major presidential candidates support the NMD.
Mr. Clinton faces not only domestic division on the NMD, but foreign relations trouble as well.
Russian president Vladmir Putin has already told Mr. Clinton he is dead-set against the American plan and has proposed an alternative plan for Russia and Europe. Russia says building a system to shoot down long-range missiles goes against the spirit and the letter of the 1972 Anti-Ballistic Missile Treaty.
If the NMD were built, China would almost certainly increase the number of nuclear missiles pointed at the U.S. (currently there are about 18) in order to be sure it could overwhelm the defense.
And if China does increase its missile fleet, some arms experts have suggested that could stoke the fires of the arms race between India and Pakistan.
"We will, if you will, kick off a domino effect of force increases in Asia," predicts arms control expert Jack Mendelsohn.
Mendelsohn also says the military's threat assessment is "based on what might be done by a country that put all of its effort into designing and building a system."
The Central Intelligence Agency says North Korea could have a missile capable of reaching the U.S. by the year 2005.
But in fact, North Korea has suspended its testing of long range missiles. Along with the regime in Pyongyang, Iraq and Iran are cited by the Pentagon as potential threats, although none has yet tested a ballistic missile capable of reaching American territory.
Even the CIA warns that an intelligence estimate based on what could happen as opposed to what is likely to happen "may prove implausible." According to the CIA, a suitcase-sized nuclear device left in the middle of a city "is probably more likely" than a missile attack.
Independent of the foreign policy and strategic calculatins, there are concerns about the accuracy of the missile interceptor tests the military has conducted.
Of the July 7 test, Tom Collina, Arms Control and International Security Program Director at the Union of Concerned Scientists said, "This test may tell us about hitting a controlled target, but in terms of a real enemy trying to attack us, this test is a joke."
As CBS News has reported, data from previous tests of the system showed an inability to distinguish between missiles and decoys.
Weeks later, the New York Times reported claims that the Pentagon's flight tests were rigged to hide the inability of the interceptor's sensors to distinguish between enemy warheads and decoys.
The Pentagon subsequently admitted that it used simpler decoys in recent flight tests of an anti-missile interceptor, but denied allegations that the switch amounted to dishonest manipulation to hide a fatal flaw.