WASHINGTON -- At the heart of the Korean crisis is the most ambitious arms-control agreement in history -- the 1970 Nuclear Non-Proliferation Treaty. It binds 163 nations, including North Korea, to prevent the spread of nuclear weapons, and it commits the five major nuclear countries -- the United States, Russia, China, France and Britain -- to share their peaceful nuclear technology with the rest of the world.
The basic commitment by non-nuclear countries that sign the treaty is "not to manufacture or otherwise acquire nuclear
weapons or other nuclear explosive devices."
North Korea signed that commitment in 1985.
But it did not accept inspections by the International Atomic Energy Agency, which monitors compliance with the treaty, until 1992.
Therein lies the crux of the crisis: What developments was North Korea pursuing in the seven years between its signing the treaty and its agreement to IAEA inspection?
The suspicion is that when it refueled its Yongbyon reactor in 1989, it separated enough plutonium from the spent fuel rods to make one or two nuclear bombs.
In 1992, the North Koreans declared that they had separated only 100 grams of plutonium during the refueling. It takes between 5 and 7 kilograms of plutonium to make a bomb.
In six trips to North Korea, IAEA inspectors found discrepancies between the Pyongyang regime's 100-gram claim and the evidence on the ground but were unable to establish the amount of plutonium extracted from the rods.
To check their suspicion that more plutonium had been removed than the North Koreans declared, the IAEA demanded this year to examine selected rods being removed from the Yongbyon reactor in the latest refueling operation, which began in May.
The North Koreans allowed IAEA inspectors to watch the rods being extracted and would not let them examine the selected rods.
The rods the IAEA scientists wanted to check were from particular locations in the reactor. They were chosen because they could have indicated more accurately how much plutonium the North Koreans removed in 1989. The rods have now been put in storage.
This raises the next issue: Will the North Koreans use the newly extracted rods to increase their nuclear arsenal despite their nonproliferation commitments? The rods, according to the Institute for Science and International Security, are likely to contain enough plutonium for four or five more nuclear bombs.
The IAEA suspended scientific aid to North Korea this week. The North Koreans responded by quitting the IAEA. But they stopped short of quitting the Non-Proliferation Treaty, a move that would divorce them entirely from nuclear safeguards.
The North Koreans actually notified the Security Council in March 1993 of their intention to withdraw from the treaty. But in June last year they suspended their withdrawal.
The North Koreans remain bound by the treaty, despite their withdrawal from the IAEA, which still has two inspectors at the Yongbyon power plant. But if they are expelled, the rods, in the words of Robert Gallucci, the Clinton administration's top Korean crisis manager, will be "completely unsafeguarded."
Mr. Gallucci, appearing on CNN last night, warned: "At this point, the North Koreans don't want to make the situation very much worse, they will leave the inspectors where they are and allow them to assure the international community that they are not moving fuel, that they are not separating plutonium."
The United States is pressing the United Nations to consider imposing economic sanctions on North Korea for defying its treaty commitments. The North Koreans have warned that sanctions could lead to war.
How have we reached this dangerous impasse with North Korea? Why have the nuclear ambitions of other countries -- Israel, India and Pakistan, for example -- not led to what former national security adviser Brent Scowcroft called on the "Larry King Live" show yesterday a "prime time crisis"?
There are three reasons, according to David Albright, a physicist with the Institute for Science and International security: The other countries have not signed the Nuclear Non-Proliferation Treaty; their plutonium production programs are smaller; they do not arouse concern about nuclear weapons exports.
"North Korea is a case of a country that might use nuclear weapons to aggressively pursue some foreign policy goals way beyond its borders," said Mr. Albright, an expert in nuclear proliferation, who said that North Korea's programs could threaten U.S. interests around the world.
Perhaps the closest parallel to the North Korean crisis is the nuclear confrontation with Iraq.
While opening its civil nuclear power facilities to inspection by the International Atomic Energy Agency after the Persian Gulf war, it kept secret a covert weapons research program.
It took an Iraqi defector from the 1991 gulf war to alert the United States to the clandestine program. Satellite surveillance confirmed that Iraq was operating secret nuclear weapons facilities in the desert. Iraq's refusal to open these to IAEA inspection led the U.N. Security Council in 1991 to impose the sort of full-scale economic sanctions being considered for North Korea.
Iran, another potentially hostile nuclear power, has opened its facilities to inspection, avoiding any major confrontation even though there is early evidence of a research program.
South Africa used a clandestine military nuclear program to develop six bombs during the 1980s, even while IAEA inspectors were checking its civil nuclear power program. But in 1991, South Africa decided to abandon its weapons program, disarmed its bombs and accepted full-scale international controls.
In Latin America, three potential nuclear powers -- Brazil, Argentina and Chile -- have all ratified the Tlatelolco Treaty, a hemispheric nonproliferation agreement which is also monitored by the IAEA.
Central to the Korean crisis are three articles of the 1970 United Nations Nuclear Non-Proliferation Treaty, which North Korea .
signed in 1985:
Article I states: "Each non-nuclear-weapon state party to the Treaty undertakes not to receive the transfer . . . of nuclear weapons . . . or of control over such weapons; not to manufacture or otherwise acquire nuclear weapons; and not to seek or receive any assistance in the manufacture of nuclear weapons or other nuclear explosive devises."
Article II states: "Each non-nuclear-weapon state party to the Treaty undertakes to accept safeguards . . . for the exclusive purpose of verification . . . with a view to preventing diversion of nuclear energy from peaceful uses to nuclear weapons or other nuclear explosive devices."
Article III states: "Nothing in this Treaty shall be interpreted as affecting the inalienable right of all the Parties to the Treaty to develop research, production and use of nuclear energy for peaceful purposes."
North Korea says that its nuclear research program is peaceful. The United States and the International Atomic Energy Association say that it is geared to develop weapons.