Americans and Asians alike are expressing relief that an agreement on North Korea’s nuclear program has emerged from the latest round of six-party talks. The agreement is certainly better than the alternatives of drift or confrontation. Nevertheless, in view of North Korea’s track record, our applause should be muted.

Under the new agreement, Pyongyang promises to shut down the Yongbyon reactor within 60 days, in exchange for 50,000 tons of fuel oil. During that period, North Korea must readmit the international inspectors it expelled in 2002, and talks will commence between Washington and Pyongyang on normalizing diplomatic relations.

This last provision echoes the 1994 “agreed framework,” which included promises of such talks but never led to meaningful negotiations. The deal is only marginally better than the framework, which froze North Korea’s nuclear program by shutting down its reactor at Yongbyon in exchange for energy aid from the United States and its allies. North Korea never fully complied last time, and the agreement broke down altogether in late 2002.

If North Korea disables its nuclear program permanently after deactivating Yongbyon, additional aid will flow, and there are hints (but no more) of additional U.S. economic concessions. The ultimate goal is an end to North Korea’s nuclear aspirations. If that occurs, we will have moved substantially beyond the 1994 agreement, in which Pyongyang agreed merely to freeze (not terminate) its plutonium program.

But the devil is in the details, and the agreement could easily break down over numerous issues in the coming months. Several matters remain disturbingly vague.

Although Pyongyang is obligated to account for the plutonium that it extracted from the Yongbyon reactor since 2002, the agreement apparently does not specify what happens to any nuclear weapons that North Korea already may have built.

That is not a trivial matter, given the evidence that Pyongyang may possess as many as 12 or 13 weapons. We certainly do not want a situation in which North Korea has merely agreed to shut down a nuclear program (and be rewarded handsomely for doing so) because it already has a credible arsenal.

Another loose end is North Korea’s alleged uranium enrichment program. It was the discovery of that program (distinct from the Yongbyon plutonium project) by U.S. intelligence agencies that led to the breakdown of the agreed framework in 2002. Pyongyang has not officially acknowledged that such a program exists, but it almost certainly does. No agreement on the nuclear issue will have much value if the uranium enrichment issue is not squarely addressed.

Most sobering of all, we must remember that North Korea has broken every agreement it has ever signed on the nuclear issue. Although it joined the Nuclear Nonproliferation Treaty, it violated that agreement on two occasions — in the early 1990s and again at the beginning of the current crisis in 2002 — before withdrawing entirely from the treaty.

North Korea signed an inspection agreement with the International Atomic Energy Agency to implement its obligations under the NPT, but then it illegally blocked inspectors in 1993 and again in 2002. Pyongyang issued a joint declaration with Seoul to keep the Korean Peninsula non-nuclear, only to repudiate that declaration in 2003. And, of course, North Korea abandoned the 1994 agreed framework.

Given that track record, it would be naive in the extreme to get terribly excited about the new agreement. It is a mildly encouraging first step, but we are still a long way from being able to say that the North Korean nuclear crisis has been resolved.