For decades, the United States maintained a strict division between its military and civilian nuclear sectors by refraining from producing materials for atomic weapons in civilian reactors.
More than symbolism and secrecy were involved. The policy was also aimed at bolstering US nonproliferation efforts by discouraging other countries from using their civilian nuclear-power facilities for military purposes.
But the Clinton administration has breached that long-standing wall for the first time, authorizing the production of tritium in three civilian reactors. Tritium is a critical atomic-weapons component of which the US is running short.
The Dec. 22 decision, which must be approved by Congress, has divided the arms-control community and added fresh tinder to a debate over whether post-cold-war US national security policies are helping fuel or throttle the global spread of nuclear weapons.
The US has been a leading proponent of nonproliferation efforts and treaties calling for the eventual elimination of nuclear weapons, and is seeking to win Russia's assent on massive new cuts in atomic warheads. But nuclear arms still play a key role in post-Soviet US security strategy, and the Clinton administration is now pursuing a $45 billion program to maintain American nuclear weapons know-how and improve the arsenal's capabilities.
Critics contend that the tritium decision will bolster those who argue that the US position is hypocritical and encourages proliferation.
Making tritium in civilian reactors "is fundamentally inconsistent with our broader nonproliferation policy," says Rep. Edward Markey (D) of Massachusetts, whose proposal to include language in the fiscal 1999 defense budget that would have blocked the decision failed. "As a weapons-state, the US cannot effectively insist that non-weapons states not use their civilian energy programs for military purposes if we engage in such a practice here at home."
Representative Markey says he intends to work to pass legislation that "would establish a general prohibition against civilian reactors ... being turned into nuclear bomb factories."
Advocates respond that by using civilian reactors, the US will avoid having to spend billions of dollars building a new military production facility that would be seen as a reaffirmation of its commitment to atomic weapons.
Such a perception, they say, would discredit US arms-control initiatives, such as the effort to persuade India and Pakistan to curb the nuclear race they uncorked with their tit-for-tat test blasts in May.
"Every step that the administration takes away from rebuilding a permanent, dedicated nuclear-weapons complex is in our view a step in the right direction," says Chris Payne of the Natural Resources Defense Council, an arms-control and environmental organization in Washington.
Under the administration's decision, tritium would be produced by the Tennessee Valley Authority (TVA) at its Watts Bar 1 reactor, near Nashville, and Sequoyah 1 and 2 units, outside Chattanooga.
The Watts Bar facility has been making the radioactive hydrogen isotope on a trial basis for 15 months in order to win Nuclear Regulatory Commission (NEC) approval of the new plan.
Tritium provides an enormous boost to the explosive yield of US nuclear weapons. It decays at the rate of 5 percent a year, requiring that it be periodically replaced. But the US closed its last tritium-production reactor in 1988 for safety reasons.
For the moment, the Department of Energy, which oversees the US arsenal, is recycling tritium from weapons it is eliminating under the 1991 Strategic Arms Reduction Treaty (START I) with Moscow. But it will need a new source of 5.5 pounds annually beginning in 2005 to support the 6,000-warhead force the treaty allows. Should Russia finally ratify the 1993 START II accord, which limits the sides to no more than 3,500 deployed warheads, a new source would not be required until 2011.
The US is now promoting a START III treaty that would cut deployed warheads on both sides to 2,000; Russian officials have spoken of 1,500 or less. Should that pact be approved, the US would not require a new tritium source until well after 2020, experts say.
"If our goal of reaching further arms-control reduction agreements is reached, we may not need to exercise this option for many years, and we will pay for tritium only when it is needed," says Energy Secretary Bill Richardson. He declined to say how much the TVA will be paid to make tritium. The TVA had been seeking $85 million per year.
Critics contend that instead of looking for ways of maintaining its nuclear stockpile, the US should be actively pursuing global disarmament.
"Renewing tritium production on any scale sends the wrong signals," says Chris Hellman of the Center for Defense Information, a policy institute in Washington. "It is provocative."
Advocates agree that the separation of civilian and military nuclear sectors is required when it comes to uranium and plutonium, the fuels that power atomic weapons. But, they say, tritium is not a controlled material and cannot itself be used to make a bomb. Canada, for instance, sells tritium commercially for various industrial uses, such as airport runway lights and luminous watches.
Mr. Payne says the administration could go further to ease the concerns ignited by its decision by asking the NEC to declare tritium a government-controlled material that can only be made in civilian reactors in national emergencies and with Congress's permission. Such an avenue would be used only when the need for a new tritium supply actually arises.
"That is a way of further demonstrating to the world that the US is buying this tritium production plan as an insurance policy against a breakdown in the disarmament process," says Payne.