Two decades after the U.S. began to scale back its nuclear forces in the aftermath of the Cold War, a number of military strategists, scientists and congressional leaders are calling for a new generation of hydrogen bombs.

Warheads in the nation’s stockpile are an average of 27 years old, which raises serious concerns about their reliability, they say. Provocative nuclear threats by Russian President Vladimir Putin have added to the pressure to not only design new weapons but conduct underground tests for the first time since 1992.

“We should get rid of our existing warheads and develop a new warhead that we would test to detonation,” said John Hamre, deputy secretary of Defense in the Clinton administration and now president of the Center for Strategic and International Studies. “We have the worst of all worlds: older weapons and large inventories that we are retaining because we are worried about their reliability.”

The incoming Republican-controlled Congress could be more open to exploring new weapons.


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FOR THE RECORD

Nuclear weapons: An article in the Nov. 30 Section A about a call for the U.S. to replace its aging nuclear weapons reported that former Los Alamos National Laboratory director Siegfried Hecker said the country could build a new generation of weapons without underground testing. Hecker, who opposes testing, believes testing would be necessary.

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“It seems like common sense to me if you’re trying to keep an aging machine alive that’s well past its design life, then you’re treading on thin ice,” said Rep. Mac Thornberry (R-Texas), chairman-elect of the House Armed Services Committee. “Not to mention, we’re spending more and more to keep these things going.”

Thornberry also offered support for renewed testing, saying, “You don’t know how a car performs unless you turn the key over. Why would we accept anything less from a weapon that provides the foundation for which all our national security is based on?”

Some of the key technocrats and scientists of the Cold War say the nation has become overly confident about its nuclear deterrence. The nuclear enterprise, they say, “is rusting its way to disarmament.”

“We should start from scratch,” said Don Hicks, who directed the Pentagon’s strategic weapons research during the Reagan administration. “We have so much enriched uranium and plutonium left from old weapons that we could use it properly for a new generation of weapons.”


In the 25 years since the Cold War ended, the U.S. has significantly retreated from the brinkmanship of the arms race, reducing its stockpile from a peak of 31,000 nuclear weapons in 1967 to its current level of 4,804 weapons. Russia has cut its stockpile to about the same size.

After the Soviet Union fell in 1991, the U.S. agreed to an international moratorium on testing, though it never ratified the Comprehensive Nuclear-Test-Ban Treaty. Halting underground tests was seen as a crucial step toward full nuclear disarmament because it would put a high barrier against developing new weapons.

The U.S. allowed much of its weapons complex to deteriorate, particularly production facilities, as cooperation with Russia flourished in the 1990s.

Today, the signs of decay are pervasive at the Pantex facility in Texas, where nuclear weapons are disassembled and repaired. Rat infestation has become so bad that employees are afraid to bring their lunches to work.


“They literally have to keep their lunch bags on a shelf that’s head high so it won’t get eaten,” Thornberry said. “They find them on their computers, in the hallways. It’s a continual problem.”

The buildings at the Y-12 National Security Complex in Oak Ridge, Tenn., are so old that a concrete ceiling recently collapsed into a production area.

The Obama administration has a $60-billion plan to modernize the Energy Department complex and update weapons, including a new type of warhead that cannibalizes components from older weapons.

The device would combine an atomic trigger from one weapon with a thermonuclear assembly from another. Called the interoperable warhead, it would reduce the number of weapons designs from seven to five, on the hopes that it would save money.


The device, which has been derided as an atomic “Frankenbomb,” has prompted criticism from arms control factions. Advocates of a strong U.S. nuclear posture are not big supporters, either.

“Mixing and mashing parts into configurations that have never been tested before is not a good idea, by any means,” said Kingston Reif, director for disarmament and threat reduction policy at the Arms Control Assn. “It’s going to cost money that we don’t have for a mission that plays an increasingly limited role in U.S. national security.”

Some of the nation’s top nuclear weapons scientists say a better option is to design new weapons better suited to current threats.

In many ways, the growing nuclear capability of China, coupled with the addition of North Korea, Pakistan and India to the status of nuclear powers, has made deterrence strategy more complicated than during the Cold War.


John S. Foster Jr., former director of Lawrence Livermore National Laboratory and chief of Pentagon research during the Cold War, said the labs should design, develop and build prototype weapons that may be needed by the military in the future, including a very low-yield nuclear weapon that could be used with precision delivery systems, an electromagnetic pulse weapon that could destroy an enemy’s communications systems and a penetrating weapon to destroy deeply buried targets.

“After more than two decades, the nuclear deterrent could be in worse shape than we want to believe,” Foster said. “We need to demonstrate the proficiency of our weapons labs and our strategic forces.”

Restarting design and production in the U.S., however, would requires billions of dollars to build new facilities, including a metallurgy plant in New Mexico for plutonium triggers and a uranium forge in Tennessee for thermonuclear assemblies.

In addition, since the mid-1990s, the National Nuclear Security Administration, the Energy Department branch that oversees the atomic arsenal, has lost some of the expertise to build weapons. Most nuclear lab scientists are older than 50, and younger scientists have no experience building a weapon.


Moving ahead with any agenda for producing new bombs will require surmounting large political, financial and technological hurdles, all of which have killed Energy Department attempts in the last two decades to design new weapons.

Norton A. Schwartz, a retired four-star general who served as Air Force chief of staff, said he sensed little support for a new round of nuclear competition. “I don’t see any appetite for breaking these taboos,” he said.

The political and environmental dynamics of testing — detonations 100 miles from Las Vegas so powerful that casinos would shake — are almost impossible to comprehend in today’s climate.

Siegfried Hecker, a former director of the Los Alamos National Laboratory and now a professor at Stanford University, said testing could cause another problem. A resumption of U.S. testing would probably prompt other nuclear powers to resume as well, allowing them to catch up with the U.S.’ huge experimental lead.


The U.S. has by far the greatest archive of test data, having conducted 1,032 nuclear tests. Russia conducted 715 and China only 45.

Hecker said the U.S. has so much experience, data and scientific capability that it could build a new generation of weapons without testing.

Advocates of a strong nuclear posture say that’s an option worth pursuing because the nation’s aging weapons cannot go on indefinitely.

Absent an international deal to eliminate every nation’s nuclear stockpile, the U.S. will eventually need new weapons to maintain its deterrent effect, even if it renews some of the fear that gripped the world in the Cold War.


“The interesting thing about a nuclear deterrent is that enough of it has to be visible to scare the living daylights out of the enemy,” said Joe Braddock, a long-time Pentagon science advisor and nuclear weapons effects expert. “But if you are not careful, you scare the living daylights out of yourself.”

ralph.vartabedian@latimes.com

william.hennigan@latimes.com

Twitter: @rvartabedian, @wjhenn