For almost three decades it has stood strong, often under attack, but always prevailing in the end.
Yet time appears to be catching up with the 1972 Antiballistic Missile Treaty, once considered a cornerstone of arms control between the United States and the Soviet Union.
Today, more than ever, the ABM Treaty is being criticized and questioned, even down to the basic point of who is party to it since the Soviet Union's collapse.
"The future is not about whether the ABM Treaty will be amended," says Baker Spring, a leading adviser to the congressional leadership on arms-control issues, "but whether there will be an ABM Treaty at all."
But unlike previous attacks on the treaty, which resulted from President Ronald Reagan's desire to build a "star wars" defense shield, this one is being joined by Democrats.
Altered playing field
Essentially, the treaty prohibits national missile-defense systems, for the reason that they would alter the balance of power between Washington and Moscow and possibly trigger a new arms race.
Yet now the playing field itself has been altered, with new threats coming from beyond the Soviet Union. Moreover, as technology has gotten better and better, pressure has built on President Clinton to move forward with the project. This summer he becomes eligible to decide to deploy a national missile defense (NMD) that would protect all 50 states from a limited attack by a "rogue" state like North Korea or Iran.
On one hand, he doesn't want to kill the popular program, because it could hurt Vice President Al Gore's chances of winning the White House. Yet Mr. Clinton also doesn't want to flagrantly violate the treaty, which specifically bars national missile defenses.
So, instead, White House lawyers are trying to push a watered-down interpretation of the treaty that would allow the nation to move forward with the early steps of deployment. In doing so, they would not have to address the more difficult subject of the treaty's actual status.
Their argument is classified and has not been adopted by the president. But it appears to be based on different perceptions of the phrase in the ABM Treaty "under construction." Clinton's lawyers essentially are saying the US can pour cement for a radar site on the island of Shemya in western Alaska without having officially begun construction.
"The US is reneging," says John Rhinelander, who, as a State Department lawyer, was a principal drafter of the treaty.
Another arms-control expert involved in writing the treaty, Spurgeon Keeny, acknowledges there is ambiguity in the three-page document, and that by some interpretations the US "could take some preliminary steps without withdrawing from the treaty."
But, he claims, "the decision will ultimately be up to the Russians" because it is a bilateral agreement.
The Republicans make a stronger attack on the treaty, arguing that it was agreed upon in a different era with a country that no longer exists.
They argue that, because the cold war has ended and technology has changed dramatically, there is no need to hold up an agreement that no longer benefits US national-security interests.
Once, that position was reserved just for the Republicans. Now there are signs that the administration is moving toward a similar track. Strobe Talbott, the deputy Secretary of State who spearheads US arms-control efforts with Russia, hinted at that this week.
"The US believes strongly that the way the world has changed since 1972 requires all responsible governments to address strategic security," he said in Oslo, Norway, where he was meeting with Russian officials.
Increasingly, defense planners are becoming concerned with rogue states and their rapidly improving missile technology. Some predict North Korea will be able to field an intercontinental ballistic missile that can carry a nuclear warhead to the US by 2005.
Furthermore, some Republicans emphasize that the Soviet Union - the nation the treaty was made with - has ceased to exist. Because the White House has not made a successor agreement with Russia, some argue that there is no valid ABM Treaty - a position that has been symbolically upheld in official meetings.
In a recent five-year review of the ABM Treaty, for example, Russia, Belarus, Kazakhstan, and Ukraine participated. But they were referred to as "sides participating in the ABM Treaty Review," not "Parties to the ABM Treaty."
Making the succession issue even more complicated, the US would need congressional approval if it were to negotiate a successor treaty. But the Republican-controlled Senate is considered highly unlikely to approve any such measure.
"I think we're getting close to getting rid of the ABM Treaty," says Mr. Spring, the congressional leadership arms-control adviser. "But it's taken a once-in-a-millennium event, like the collapse of the Soviet Union, to do it."
(c) Copyright 2000. The Christian Science Publishing Society