Clouds of good cheer billowed out from Pyongyang and Beijing this week, giving rise once again to the hope that maybe, just maybe, peace is at hand on a Korean peninsula freed of nuclear arms.

Amid this optimism, it may be curmudgeonly to say so but the history of dealing with North Korea over six decades justifies a dose of skepticism. That path is strewn with North Korean deception, lies, broken promises, assassinations and attempted assassinations, kidnappings, other violence, and no small amount of belligerent bluster.

In Pyongyang, a summit meeting between President Roh Moo-hyun of South Korea and Kim Jong Il, who was billed as chairman of the North Korean National Defense Commission, produced an agreement declaring "a new era of national prosperity and unification."

In Beijing, representatives of China, South Korea, North Korea, Japan, Russia and the United States in the Six Party Talks produced a consensus on actions, "the goal of which is the verifiable denuclearization of the Korean peninsula in a peaceful manner."

Diplomatic declarations often suggest that what was not said could be even more significant than what was said.

President Roh and Chairman Kim said, for instance, they would make "joint efforts" to find a solution to the nuclear problem on the Korean peninsula." The "nuclear problem" is that North Korea has pushed ahead with acquiring nuclear weapons to the point of having tested a nuclear device a year ago.

Chairman Kim and President Roh said nothing about North Korea giving up its nuclear weapons or shutting down its nuclear facilities as demanded by the other five nations in the talks.

Moreover, the Foreign Ministry of China and the State Department of the U.S. each released statements on the outcome of the four days of negotiations in Beijing. The North Koreans in Beijing, as has often been their practice, said nothing, which left them open to issue their own interpretation of what was agreed, as they have in the past.

Further, the State Department's "fact sheet" included a curious provision, saying that actions to shut down the North Korean nuclear plant at Yongbyon were "to ensure that the DPRK (Democratic Peoples Republic of Korea, the proper name for North Korea) would have to expend significant time and effort to reconstitute its ability to produce weapons-grade plutonium."

That sounded as if the U.S. had given up on making the shutdown of Yongbyon "irreversible," as Washington once demanded, and left a hole through which the North Koreans could slip if they sought to rebuild their capacity for making nuclear arms.

On another issue, President Roh and Chairman Kim agreed they needed to "put an end to the existing armistice mechanism and build a lasting peace mechanism."

A touch of history is required here. At the end of the Korean War of 1950-53, North Korea, China and the United Nations Command led by the U.S. signed an armistice, not a peace treaty. Technically, the Korean War is still going on.

More to the point, South Korea is not a party to the armistice because the formidable Syngman Rhee, then president of South Korea, refused to sign it. It is therefore up to the North Koreans, Chinese and U.N./U.S. to work out a peace treaty, which was left out of the Roh-Kim agreement.

President Roh pressed President Bush, when they met in Washington last month, to state clearly that the U.S. would negotiate a Korean peace treaty. Bush demurred: "We look forward to the day when we can end the Korean War. That will end — will happen — when Kim Jong Il verifiably gets rid of his weapons programs and his weapons."

The summit declaration included a statement that would be laughable if it were not so sad. It said that North Korea and South Korea agreed to push ahead in "humanitarian cooperation." Yet Kim Jong Il's regime is surely among the most oppressive in the world.

Between 1 million and 2 million North Koreans have died of starvation in recent years because the Kim government has so mismanaged the economy, particularly agriculture, and has hampered outside efforts at relief. In addition, an estimated 200,000 North Koreans are held as political prisoners.

Peter Beck, an experienced Korea hand and executive director in Washington of the U.S. Committee for Human Rights in North Korea, has pointed to Pyongyang's "vast and inhumane gulag system for political prisoners" and its redirection "of food aid for other purposes while its people go hungry."

Richard Halloran is a Honolulu-based journalist and former New York Times correspondent in Asia.