We have no hope of reducing the missile threat -- or dealing with a number of critical issues -- unless we constructively engage North Korea. A reversal by the Bush administration puts that policy of engagement at risk and is troubling news for all those concerned with our interests on the Korean peninsula. Two days before President Bush met with South Korean President Kim Dae Jung, Secretary of State Colin Powell stated that the Bush administration would "pick up" where the Clinton administration left off. Two days later Bush directly told President Kim the opposite, and announced publicly that we would not resume missile talks with North Korea any time soon. Many of us were left wondering what had changed in the space of two days.

America's foreign policy interests in the region remain a high priority -- as they have been from the time we lost nearly 60,000 lives there a half-century ago ago.

The Clinton administration left a bargaining framework on the table that could, if pursued aggressively by the Bush administration, go a long way toward reducing the threat posed by North Korean missiles and missile exports.

Our South Korean allies -- on the front lines and under no illusions about the regime in North Korea or its leader, Kim Jong Il -- want us to move quickly to resume the missile talks. President Kim firmly believes that Washington and Seoul must continue their efforts to open up North Korea. We should listen to him carefully.

Secretary Powell has asserted that some of the things put on the table by the Clinton administration are "promising," but that monitoring and verification "are not there." He says the news administration plans to do a comprehensive policy review before deciding when and how to engage North Korea.

We can all be sympathetic to the Bush administration's desire to study the proposals left on the table by the previous administration. But even while analyzing new proposals, what better way to test the possibilities than by maintaining an open dialogue? That way we avoid losing a window of opportunity -- and even sending the wrong signal to Pyongyang -- by delaying too long.

Over the past eight years, North Korea has taken previously unimaginable steps. It has agreed to freeze its existing nuclear energy program under supervision and permit inspection to determine the past operating history of its reactor program just prior to the delivery of key components of light-water reactors.

When the United States suspected North Korea was violating the agreed framework by building a new reactor in an underground site, North Korea agreed to allow American inspections -- proof that monitoring and verification agreements can be negotiated with North Korea. By the eleventh hour of the Clinton administration, we were discussing proposals to prevent North Korea from developing missiles capable of striking the United States and to bring a halt to North Korea's lucrative missile exports.

We should be encouraging Pyongyang to continue on this path. Delaying missile talks is a mistake. In fact, delay -- and Secretary Powell's lukewarm endorsement of the agreed framework -- could send a negative signal about the nature and direction of our policy.

While the Clinton administration moved faster in the missile talks than some believe prudent, nothing has been agreed to that ties the hands of the Bush administration. Negotiations have simply begun, and proposals are on the table. Nothing precludes this administration from making new proposals on monitoring and verification -- indeed, it should. But that cannot happen if discussions are in limbo.

North Korea's missile capability is an important question not only with regard to security on the Korean peninsula but also to our own debate on national missile defense. The Bush administration points to the North Korean missile threat as a major reason why we need to proceed with such a defensive system. This makes its hesitant approach on missile talks with Pyongyang all the more puzzling. If we can reduce or eliminate the threat posed by North Korea's missile program, why wouldn't we push ahead? Not only would we have greater security but we'd be able to examine national missile defense options that may be less costly and damaging to the arms control regime established by the 1972 Anti-Ballistic Missile Treaty.

There is little to lose and much to gain by returning to the bargaining table. There is considerable risk in leaving the North Korea missile threat to chance.

The writer is a Democratic senator from Massachusetts and a member of the Senate Foreign Relations Committee.