When and if serious defects are found in secondaries, NIF’s contribution to fixing them would probably be minimal. According to the “Programmatic Environmental Impact Statement” published by DOE in September 1996: “If an unanticipated change relevant to the high-energy-density phase of weapon operation is observed in the weapon surveillance program [SEP], specially designed NIF experiments could aid weapons scientists in validating aspects of their integrated computer models to assess whether that change would adversely impact the weapon’s reliability.”
The trouble with this justification is that it is not clear how helpful NIF would be in assessing age-related changes. Moreover, such assessments are not even necessary. A simpler approach is merely to build a new part. If the labs are unsure how significant a defect is, the management program can have a replacement part manufactured at the Oak Ridge plant in Tennessee, which will maintain its capacity to build secondary components. According to the Pentagon’s Smith, “The way you take care of aging is, in extremis, you build a new one. And that’s what we’ll do.” Alternatively, the part could be replaced by a spare in reserve.
Proponents also suggest that experimental results from NIF could be used to improve computer codes to determine whether rebuilt parts would behave as expected. But that is not a great concern for secondaries. According to a Los Alamos scientist, “secondaries are much more forgiving than primaries.” And incorporating NIF data into these codes would entail some risk. Computer codes for designing and simulating nuclear weapons have been “normalized” to nuclear test results-that is, the codes are based on data from actual explosions. Modifying the codes on the basis of NIF experiments could distance them from past test experience, possibly rendering them less reliable.
If NIF is not needed to fix warhead problems, then why do we need it at all? According to DOE, the broader NIF stewardship mission is to act as a “magnet” to draw fresh talent to Livermore and keep current weapons designers engaged, making it easier to assess warhead problems and design new warheads if international relations go sour. As Victor Reis, assistant secretary of energy for defense programs and architect of the stewardship program, testified before Congress in 1994: “The whole idea of lasers is for understanding the physics of secondaries, but also more particularly, for maintaining that cadre of scientists who both understand the fusion process and all the things that go along with that… . The stewards really are more important than the equipment.”
But while NIF may succeed in attracting new talent to work on nuclear physics, it is not clear that it would attract people who want to do weapons work. Supercomputer experience is more relevant to the career of a budding weapons designer than a job pushing the envelope of fusion research. So it seems likely that the $93 million IBM supercomputer Livermore is due to receive in 1998-a machine that will run 300 times faster than any existing computer-will play more of a “magnet” role than NIF. If we are genuinely concerned about maintaining expertise in weapons physics, $4.5 billion in salary increases for weapons designers might be money better spent.
But perhaps the concern itself is misguided. If more nuclear weapons were needed in a renewed Cold War, the United States could build them using existing designs, a job that would not require advances in nuclear weapons physics. In the worst and most unlikely case-new types of warheads are needed to counter an adversary’s qualitative leap-design teams could be reconstituted at the labs, which, even without NIF, will employ weapons scientists in design-related activities. The experience gained from the more than 1,000 nuclear tests the United States conducted before the cessation of such activities, plus the renewed testing that would clearly be warranted in such a crisis, would give the reconstituted design teams a huge database on which to draw.
Many scientists outside the defense arena find NIF very exciting. If successful, its increased power and greater implosion symmetry over Livermore’s NOVA could make it the first fusion facility to achieve ignition-a state in which more energy is produced than is needed to create the reaction in the first place. This would be an important milestone in the development of fusion power for civilian energy production. But there are two problems with using the prospect of civilian fusion experiments to justify NIF. One is a matter of prudence, the other a matter of public accountability.
Investing huge sums in a fusion facility is a risky proposition. For one thing, there is no guarantee that NIF, even with its 192 separate beams, can achieve the exquisite symmetry of implosion needed to produce an efficient fusion reaction. Timothy Coffey, director of research at the Naval Research Laboratory, who served on a 1994 NIF review panel, has expressed doubts about the prospects for success, adding: “If ignition is not achieved, then more than one billion dollars will have been wasted since the residual capabilities of the facility could have been far more easily achieved by different and much less expensive techniques.”
Exemplifying the technical difficulties the project could face, a glass lens in a NIF prototype laser imploded in September, causing the laser to be shut down for the second time in 17 months. Researchers have less than a year to correct the problem before construction begins.
Many other obstacles must also be overcome before fusion energy runs our refrigerators. Lasers are not expected to meet the requirements-efficiency, high rate of repetitive firing, and long lifetime-of a future fusion energy source. Other means of driving the reaction, such as a heavy-ion accelerator, may have to be developed. A 1995 Energy Departmentsponsored task force chaired by Robert Galvin of Motorola warned-even though it ultimately favored NIF-that “there is a low probability that inertial fusion will become a useful source of energy in the foreseeable future.”
Still, NIF has become a favorite of researchers in a number of basic and applied science areas. It could yield insights into supernovas, for example, as well as aid in the study of materials under high pressure, dense plasmas, and radiation sources. Prominent physicists recently wrote to Rep. Ron Dellums (D-Calif.), the ranking Democrat on the House National Security Committee, urging his support for the project on the grounds that it would be “important to fusion energy and basic science.”
This is where accountability comes in. NIF may be a great asset to fusion research and other fields, but it is not being funded as a basic-science tool. The facility has been promoted for its nuclear-stewardship role first and its civilian role second. So if the program’s real value stems from its contribution to basic science, then it ought to be subjected to the same funding criteria as other large basic-science projects. Would NIF survive close congressional scrutiny if it couldn’t hide behind a national security smoke screen? The cancellation of the superconducting supercollider is proof enough that expensive basic-science projects are a hard sell in Congress these days.