The United States today is an extraordinarily secure nation. With the end of the Cold War and the US victory in the Gulf War of 1991, US power appears to be unchallengeable. But there are dangers on the horizon. Possible adversaries, having learned from Saddam Hussein’s mistakes during the Gulf War, are unlikely to confront the United States directly. Instead, they will probably resort to “asymmetric” strategies, approaches that enable them to focus on US vulnerabilities. A particularly dangerous asymmetric threat arises from the proliferation of ballistic missiles, especially if they are equipped with nuclear, chemical, or biological warheads. But despite the fact that 74 percent of the American people believe the US is defended against such a threat, little has actually been done. The United States remains vulnerable to ballistic missile attack.

During its first few years, the Clinton administration cut funds for promising BMD programs inherited from the Reagan and Bush administrations. Indeed, only a handful of congressional Republicans kept the issue of missile defense alive. But in 1998, the country received a wake-up call with the report of the Rumsfeld Commission, which concluded that the lead time for developing ballistic missiles was much shorter than the administration was reporting. This was followed shortly by North Korean and Iranian missile tests. In response to these events, Congress passed the 1999 National Missile Defense Act, which the president reluctantly signed into law (PL 106-38).

This reluctance is indicative of a widespread resistance to the idea of ballistic missile defense. Opponents usually couch their objections in terms of cost and technical difficulty. Critics cite the recent test failure of an interceptor for the proposed national missile defense system as an example of why ballistic missile defense (BMD) is “too hard to do.”

But the US aerospace industry is the envy of the world. It has made spectacular advances in missile defense technology. And tests are designed to identify problems. Failures are positive when they identify problems that need to be corrected while demonstrating that a system is still on track. For example, the interceptor for the Theater High Altitude Area Defense (THAAD), the improved Patriot (PAC-3) experienced failures in early tests that have since been corrected.

The most recent test failure was the result of a malfunction in the Minuteman booster that prevented deployment of the kill vehicle. This indicates problems with engineering or quality control, not with the anti-missile technology itself. After all, hit-to-kill technology was demonstrated fifteen years ago. “The thing that failed in this test,” said Sen. Jon Kyl of Arizona, “is something that we’ve done hundreds of times before.”

But all the alleged concern about test failures is a smokescreen. The real reason that the Clinton administration and its allies have only reluctantly moved toward BMD is that the most promising technologies might violate the 1972 Anti-Ballistic Missile Treaty (ABMT). The Clinton administration’s approach makes sense only in the context of its commitment to this treaty. Indeed, the administration’s overriding concern has not been how to devise the best possible defense system in order to meet the emerging threat, but how to avoid or minimize revisions to the ABMT. As a result, the United States is well on its way to creating a limited system that would do little to defend the US homeland while leaving our friends and allies unprotected altogether.

Such an approach is unsatisfactory. The US should be pursuing a robust and effective BMD system driven by technological considerations and potential threats rather than the provisions of an obsolete arms control agreement that even its author, Henry Kissinger, believes should be abandoned. Such a system would be layered, providing multiple opportunities to intercept a missile and its payload over the course of its flight, beginning with launch. It would go far beyond what the Clinton administration wants, employing sea- and space-based components.

The conventional wisdom holds that the ABMT is the “cornerstone of strategic stability.” Without it, say opponents of missile defense, Russia and China will expand their nuclear arsenals, setting off a new nuclear arms race. But neither Russia nor China have ever been constrained by scraps of paper before, and they will most likely do what they want whether the US is abiding by the ABMT or not. While the ABMT does little to affect the actions of potential missile proliferators such as Russia, China and North Korea, it has a tremendous impact on US missile defense programs. A case in point is its effect on a promising system known as SBIRS-Low.

The heart of any effective missile defense program is a system of external sensors that would permit early detection and destruction of a ballistic missile. The Space-Based Infrared System (SBIRS-Low) provides such a capability. SBIRS-Low is a proposed constellation of low-orbiting satellites that use infrared technology to detect missile launches and then track missiles throughout their flight, transmitting the data to whatever anti-missile system is deployed, from the Navy’s “Aegis plus” to the most sophisticated space-based laser. But now SBIRS-Low is on hold. One cannot escape the conclusion that a major reason for this action is that the ABMT prohibits the use of external sensors.

The United States should pursue a robust and effective missile defense system that employs the most promising technologies whether they are permitted by the ABMT or not. If is does not, the “indispensable” nation will increasingly become vulnerable to this asymmetric threat. This vulnerability will adversely affect the role the US plays in the international arena, possibly making it a less reliable ally, or even causing it to retreat into isolation. Without American power to underwrite it, it is unlikely that the liberal world order we take so much for granted will long endure.

Mackubin Thomas Owens is professor of strategy and force planning at the Naval War College in Newport, RI, and an adjunct fellow of the Ashbrook Center. The views expressed here are his own and do not reflect the position of the War College, Navy Department, or Department of Defense.