This is an extraordinary moment in the relationship between the two Koreas. Last week, for the first time since 1945, North and South Koreans jointly commemorated their liberation from Japanese colonizers at the end of World War II in Seoul. The North Korean delegation visited the South Korean Parliament, another first. The two countries also staged a joint football match where 50,000 spectators chanted, "Unified Korea, Unified Korea." The lovefest doesn't stop there. Trade is reaching new heights. Cooperation across the demilitarized zone is proceeding at dizzying speed.

Good news for the future of peace on the Korean Peninsula? Not necessarily. Nowhere in the lavish speeches and statements of mutual affection was the thorny issue of Kim Jong Il's nuclear aspirations mentioned. The omission was glaring, given that the North Koreans were in town as part of the Six-Party Talks, the multilateral negotiations designed to convince Pyongyang to relinquish its weapons. The Beijing talks--which involve the United States, China, Russia and Japan as well as the two Koreas--are scheduled to resume at the end of this month. But increasingly observers are asking whether their purpose is to de-nuclearize the Korean Peninsula--or merely to satisfy each country's domestic political concerns.

The immediate sticking points are obvious. The most important is a disagreement over whether North Korea should be allowed to retain any of its nuclear expertise to generate energy. Russian presidential envoy Konstantin Pulikovsky, who met with North Korean dictator Kim Jong Il several days ago, said that Kim insisted his country should "further develop the nuclear energy sector for peaceful purposes"--a desire Kim directly related to "difficulties in the country's economy." That's an argument the Bush administration and the conservative Japanese government are not likely to buy. They both argue that North Korea has a history of cheating on past commitments, meaning that even an ostensibly civilian nuclear industry could be easily support a covert weapons program.

There could, at least theoretically, be ways out of that impasse. South Korea has tried to smooth the path to an agreement by offering to supply the North with two gigawatts of electricity from its own grid--even though there are indications that the North Korean system may not be able to handle the inflow. Another way to dodge the issue, says Hayes, might be to create a reactor complex inside North Korea that would be staffed by South Koreans or international personnel and subject to strict International Atomic Energy Agency controls. Kim Jong Il made a point of telling Pulikovsky that North Korea could soon rejoin the nuclear Non-Proliferation Treaty if conditions were right.

Then there's the problem of "sequencing." The Americans at the negotiating table insist North Korea should receive aid only once the country has taken measures to get rid of its weapons. The North Koreans, predictably, would like to see concessions up front, as a sign of good will, before they actually do anything. That's a procedural issue that could probably be worked out by fudging the timing to look simultaneous. Indeed, U.S. envoy Christopher Hill sounded optimistic last week when he talked about the possibility of reaching an agreement as early as September.

Talk to the experts, though, and the prognosis is much more gloomy. Doubters argue that all six parties came to the table with agendas that, in many respects, continue to diverge. The Chinese and the Russians would like to see the North give up its nukes but are equally interested in maintaining the stability of Kim Jong Il's regime for fear of the chaos that might ensue if the communist government were to collapse completely. Whatever their public pronouncements, meanwhile, many American officials doubt that Kim will ever give up his nukes--meaning that regime change is the only way out.

In that case, why come to the table? Basically, say observers, everyone involved benefits from making a good show of things. By demonstrating that it's willing to pursue serious negotiation, Washington can subsequently argue that it has been willing to exhaust all the options--a key diplomatic move if the Bush administration decides that it wants to start pushing for U.N. sanctions against the North Koreans. The Chinese and Russians maintain the status quo. The Japanese can talk tough about citizens kidnapped by Pyongyang decades ago, without making any hard decisions about its military stance toward the North. And the ruling Uri Party in South Korea can show its increasingly anti-American base that it can mediate between Washington and Pyongyang.

The North Koreans, in turn, gain plenty just by showing up. They've already received the electricity pledge, additional food aid and rapidly widening cooperation in a variety of spheres from South Korea. And participating in the talks is also a great way to deepen the split between Washington and Seoul. Just before the inter-Korean festivities last week, Seoul's Unification Minister Chung Dong Young gave his stamp of approval to Pyongyang's demand for a peaceful nuclear program--thereby placing his government directly at odds with the United States. "Minister Chung's remarks undermine an already shaky South Korea-U.S. alliance," says Ryoo Kihl Jae, a professor at the University of North Korean Studies in Seoul. "The North will try to take advantage of the situation in the Six-Party Talks." The North's delegation certainly leapt to the occasion during its visit to Seoul. At a solidarity rally involving workers from both countries, Northerners shouted that "U.S. troops object to unification," while Southerners chanted, "Let's kick out all U.S. troops and achieve unification through our own efforts."

The danger is that the more reasonable the North Koreans seem, the less likely it is that they'll be forced to abandon their nuclear program. Many South Koreans tell pollsters they feel more threatened by American hegemony than by the North's nukes. "South Korea's mainstream has changed from an anti-Pyongyang to a pro-Pyongyang group," says Ryoo. "The two Koreas have become closer because the South, not the North, has changed." That in turn has stiffened Washington's position. "The U.S. basically doesn't trust South Korea," says Peter Hayes. "Many of those [in the Bush administration] who hold very hard-line positions on North Korea are also deeply skeptical of South Korean intentions and believe that regime change has to come first in South Korea, then in the North."

Pyongyang seems well aware of its options. In a covertly videotaped interview provided to NEWSWEEK by the Japan-based human-rights group RENK, a senior North Korean official accuses China of backsliding under U.S. pressure. His take on Seoul is striking: "I was surprised to learn how favorable South Korea is towards us," he says. "South Korea has begun to say, 'We don't need the U.S. any more. We will solve the problems on our own'." The way things are going, that could be no solution at all.