The North-South declaration is an ambitious document that tries to take not a small step, but a dramatic leap forward to the final goal of ending the Cold War. It deserves credit for its reach, but ultimately it will not cross the finish line anytime soon. Following on from the July 20 shutdown of North Korea's main nuclear reactor facilities at Yongbyon, the six-party "second phase" agreement specifies a complete declaration by Pyongyang of all its nuclear activities, including fissile materials, and a permanent disablement of those facilities by Dec. 31, 2007.

The next three months of implementation will no doubt be difficult and may be subject to unseen delays, but once disablement is complete by the end of 2007, we would enter the "endgame" in Bush's last year which would be the final negotiation to dismantle and remove the nuclear weapons. Should this be achieved, it would be an unprecedented case of nuclear rollback surpassing that of Libya.

Despite these achievements, criticism from all circles undoubtedly will continue. For liberals, the agreement spotlights Bush's wholesale abandonment of his earlier irresponsible hardline policies that left the North to explode a nuclear device one year ago. Conservatives criticize the agreement because it allows the North to continue to hide its newer covert uranium-based nuclear activities while it gives up an old and largely broken facility.

Both views are wrong. "Disablement" -- the step before dismantlement -- is a counter-proliferation concept that came out of Bush's first term emphasis on a complete, verifiable, and irreversible dismantlement (CVID) of North Korea's nuclear programs, so there is more continuity here than liberals acknowledge.

Moreover, achieving disablement of the decrepit Yongbyon reactor facilities is still useful if one considers that any plutonium that can still be produced there has a half-life measured in the thousands of years. Permanently disabling these capabilities means no more North Korean plutonium that could be around for generations for others to lose or use. That's good for South Korean national security.

Additionally, U.S. experts are in North Korea for a second unprecedented visit to inspect aluminum tubes that may be part of Pyongyang's covert uranium-based activities, which would demonstrate measurable progress on a complete nuclear declaration. The inter-Korean declaration offered no surprises. It represents a good statement of Korean aspirations, not unlike the tone expressed in the July 1972 and June 2000 inter-Korean declarations. Two things however are noteworthy.

First, the document absolves South Korea from intervening in the North's internal affairs. This statement runs completely counter to the 2005 Bush-Roh Joint Declaration at Gyeongju where the Roh government expressed for the first time its concern for the well-being of the people of North Korea. This was a major statement by Seoul that I personally took painstaking hours to negotiate. How can Seoul have two inconsistent positions on North Korea human rights abuses in arguably the two most important joint declarations the Roh presidency has overseen?

Second, South Korean officials de-briefed in Washington the week after the summit, and made a clear push to get the American president to agree to a three- or four-way summit to end the Korean war. Not surprisingly, this request is being met by strong resistance by both Republicans and Democrats because they all follow the same logic: A peace treaty signed by a U.S. president before North Korean denuclearization will ensure that North Korea will never denuclearize.

The key driver of any peace treaty process has and will remain the full denuclearization of the North. Until all the nuclear weapons are removed from North Korea, there will be no end to the Cold War in Asia. The estimated US$11 billion in South Korean economic assistance that will go north as a result of the joint declaration should have given Seoul the leverage to negotiate better language to take into account Seoul's equities with the U.S. and other partners.

But the bottom line is that this is a document negotiated by Roh, but implemented by his successor, who is likely to be a conservative. A future South Korean government will still seek engagement with the North but will seek to coordinate any inter-Korean aid with progress in six-party talks. If the next South Korean president does this, then the carrots offered by Roh Moo-hyun will become very powerful bargaining chips in the final phase of the six-party negotiations to achieve nuclear rollback in North Korea next year. That is a finish line worth crossing.

Victor Cha is a professor and Director of Asian Studies at Georgetown University. He served on the National Security Council from 2004 to May 2007 and was deputy head of the U.S. delegation to the six-party talks.