Yesterday's joint declaration by the leaders of North and South Korea after their summit in Pyongyang came hard on the heels of the announcement that North Korea is to disable its nuclear reactor and completely account for its fissile material by the end of the year, as already agreed in the six-nation multilateral talks. Together these two developments represent the greatest change in their relations since the end of the Korean war in 1953 imposed a tense standoff on the peninsula.
If the agreements are adhered to the prospect of a prolonged period of gradually improving relations between them is opened up, leading to possible unification over the next generation.
This was only the second Korean presidential summit. The previous one, in 2000, was much more symbolic. This one must be judged on its substance, which is substantial. The eight point declaration covers the search for a permanent peace agreement and a formal end to the Korean war, security and military affairs, economic, investment and trade relations, reuniting divided families, air and rail transport, joint fishing arrangements, language, sports and cultural co-operation, and science and technology. These are general statements, many of them aspirational, which will require detailed negotiations to refine and implement. But there are commitments to more regular summits, prime ministerial and ministerial meetings, so the framework for progress has been laid down.
Critics of the two agreements urge caution, since the North Koreans are notoriously tricky negotiators and are presumably motivated by the need for massive aid to prop up their ailing economy. Too open a process of change would undermine them politically, taking away the isolation and xenophobia on which the Stalinist state has relied for popular support. In the same way, their enduring need for a nuclear card with which to browbeat those negotiating with them into giving economic aid means it is by no means certain they will agree to relinquish their existing stock of nuclear weapons even if they do disable their nuclear reactor.
Notwithstanding such doubts the South Koreans have welcomed President Roh Moo-hyun's achievement in securing such a comprehensive programme of action. Party opponents say he may have been too soft on the North Korean president Kim Jong-il because he has only four months left in office; but there is overwhelming support for some such process of gradual improvement in relations as the best way to head off the tremendous shock a more rapid unification would have on far more prosperous and developed South Korea.
President Bush has also taken a risk in endorsing the nuclear deal without a cast iron guarantee that it will be implemented. It is worthwhile nonetheless, since complete certainty is not available in such talks, which must be based on an element of trust. And Mr Bush is right to say the Korean agreement could be a template for a similar approach to Iran. Multilateral diplomacy works.