The Bush administration was right to participate in talks in Beijing last week over how to resolve the serious threat posed by North Korea's nuclear program. The first round of talks, last April, ended acrimoniously. This round, which was expanded to include not only China but also Japan, South Korea and Russia, ended with an agreement to hold another round of talks within two months.

It may not sound like progress - especially when one considers that the other major news from the conference was the North's brazen threat to test a nuclear weapon unless Washington agrees to sign a nonaggression pact. But if an agreement to talk further is evidence of the Bush administration's new willingness to engage the North, then that is good news.

As the administration prepares for the next round of negotiations, it must decide what it ultimately wants them to achieve. This will be no small challenge for an administration that, despite tough public pronouncements, continues to be badly divided between hard-liners who have pushed to isolate the North (with the eventual goal of regime change) and other officials who favor engagement because they believe isolation could lead to a catastrophe.

Hard-liners viewed last week's talks as an unwanted but unavoidable step in a policy ultimately intended to isolate the North in the hope of forcing the collapse of Kim Jong Il's regime. This policy calls for negotiation to fail by setting an unrealistically high bar for success - specifically that North Korea unilaterally dismantle its nuclear program completely before the United States will even consider subsequent talks about its security, a nonaggression pact or economic support.

This position is unacceptable to Pyongyang for obvious reasons. And when the North fails to capitulate, so the thinking goes, the Bush administration will be better placed to turn to its allies and demand they embrace a policy of isolation, having demonstrated the North's intransigence. At the moment, America's allies are against isolating Pyongyang - a position they forcefully expressed to Washington again last week.

On the other side of the spectrum is the pro-engagement camp, which believes that engagement - backed by deterrence - is the only realistic option. This includes addressing North Korea's security concerns in a meaningful manner. As distasteful as it may be to negotiate with North Korea after it failed to abide by the terms of the first nuclear pact it signed in 1994, this camp believes that ultimately there is little choice.

This position is based on two considerations. First, a policy of isolation will put a heavy strain on Washington's relations with Beijing, Moscow, Seoul and, to a lesser extent, Tokyo, all of which have stated at one time or another that they want to avoid a showdown with the North (although Japan has recently demonstrated more of a willingness to support Washington). Second, Mr. Kim, the North Korean leader, is unlikely to go down without a fight.

The costs of a military confrontation are unimaginable - politically and economically. In 1994, the United States military commander in South Korea estimated that a war with the North would result in one million deaths (including tens of thousands of Americans) and cost the United States at least $100 billion.