for nuclear weapons is more widely available
USATODAY, February 26, 2003. Updated February
By Peter Eisler
Original address: http://www.usatoday.com/news/world/2003-02-26-nuke-threat-cover_x.htm
WASHINGTON — U.S. officials have insisted
for a decade that getting plutonium or highly enriched uranium is the
big hurdle for rogue states or terrorists trying to build nuclear weapons.
But for much of that time, they've known a secret: Other materials can
be used to make atomic bombs, and they're a lot easier to get.
Now, officials believe the bad guys know the secret
Classified nuclear threat reports warn that rogue
countries and terrorists have learned it is possible to make atomic
bombs using low-enriched uranium, a common fuel for nuclear reactors
used to conduct research and generate power. The reports, described
to USA TODAY by top federal officials, also conclude that it would be
easier than previously believed for enemies of the United States to
make such weapons using spent nuclear fuel, the waste generated by reactors.
(Related item: Ways
to make a nuclear weapon)
Neither of those substances is listed as "weapons
usable" under U.S. or international security protocols. As a result,
they get little protection from theft at civilian nuclear reactors worldwide.
That includes reactors in former Soviet states and nations such as Indonesia,
where public sympathy runs high for Iraq and al-Qaeda.
And the threats are real.
Five years ago, U.S. scientists at Los Alamos National
Laboratory secretly designed an atomic bomb with low-enriched uranium,
USA TODAY has learned. The bomb, which could have fit easily in a small
pickup, was weak in nuclear terms but strong enough to destroy a square
mile of a city.
U.S. scientists also have proved in experiments
that it is possible to create nuclear weapons using several elements
that could be extracted from spent fuel by a rogue state or perhaps
even a well-organized terrorist organization.
Officials stress that there is no evidence that
al-Qaeda or any other terror group has the skills or tools to build
an atomic bomb using low-enriched uranium or spent fuel. There's a big
gap, they say, between knowing such things are possible and being able
to do them. Rogue states are a bigger concern: U.S. officials believe
that Iran and North Korea are trying to develop the capability to make
nuclear weapons using spent fuel.
Yet U.S. efforts to stop the spread of nuclear weapons
still focus almost exclusively on protecting plutonium and highly enriched
uranium, the traditional "weapons usable" nuclear materials.
That atomic bombs can be made with little or none of those substances
reveals significant gaps in current programs to keep rogue states and
terrorists from developing a nuclear capability.
Under U.S. and international protocols for protecting
nuclear materials, facilities handling low-enriched uranium or spent
fuel are not obliged to have armed guards or security systems to stop
break-ins or insider thefts. Such measures are expected of nuclear installations
holding plutonium or highly enriched uranium. Accounting and inventory
rules also are far less stringent for material not deemed "weapons
Officials at the International Atomic Energy Agency,
the arm of the United Nations that monitors nuclear stocks worldwide,
say such distinctions are appropriate because plutonium and highly enriched
uranium remain the most effective and easy-to-use materials for making
"We work on the assumption that rogue states,
or terrorists for that matter, know how to make (nuclear) weapons with
small amounts of material and different types and combinations of material.
But we've been advised by experts with the nuclear weapons states that
it would be very difficult," says Davis Hurt, a senior safeguards
expert at the agency.
The agency, based in Vienna, has to focus its oversight
on the biggest threats, Hurt says. Expanded monitoring of other materials,
such as low-enriched uranium, wouldn't be possible unless the agency's
member states provided money to boost its budget, he says.
Cracking nuclear myths
From the dawn of the atomic age, nuclear weapons
have relied on plutonium or highly enriched uranium for their explosive
Highly enriched uranium is easier to make and to
use. It is created by processing natural uranium to boost its concentration
of uranium-235, the element's most fissionable isotope. Once that concentration
is sufficient, it's relatively easy to make a "gun-type" atomic
bomb, which slams masses of enriched uranium together in a gun barrel-like
tube. That was the type of bomb the U.S. dropped on Hiroshima in 1945.
Plutonium is more of a challenge to make because
it requires running uranium through a nuclear reactor. It's also harder
to fashion into a bomb: a plutonium "pit" has to be surrounded
with conventional explosives that are precisely detonated to compress
the material and create a critical reaction. But plutonium weapons yield
much bigger blasts with far less material.
In the 1960s, as nuclear power went global, U.S.
officials successfully pushed for international standards to keep plutonium
and enriched-uranium stockpiles secure. The International Atomic Energy
Agency monitors compliance with voluntary measures through inspections
and inventory checks. Physical protections — guards, gates and
guns — are the responsibility of each nation, and the agency cannot
mandate such measures.
The agency's protocols and inspection programs fail
in several ways to account for types and amounts of materials that can
serve as fuels for a nuclear device:
- Low-enriched uranium, or uranium containing
less than 20% of the U-235 isotope, is not labeled "weapons usable"
under either U.S. or international standards. Reactors using the fuel
are inspected once a year versus once a month for those using plutonium
or highly enriched uranium. They also have more leeway in accounting
for material that goes missing.
Many of the world's research reactors use low-enriched
uranium with U-235 concentrations just below 20%. That material can,
as Los Alamos proved, create a nuclear blast, though making a bomb with
it requires substantial skill and a relatively large amount of material.
The United States helped convert many of those reactors from highly
Some reactors run on uranium enriched to less than
5%, which cannot sustain the critical reaction for nuclear weapons.
But even that material would carry risks in the hands of a rogue state
because it is relatively easy to boost its enrichment enough for weapons
"If you got a stack of uranium enriched to
4-5%, which as a rule is not seriously protected, the plant needed to
convert it to 90% enrichment is potentially small and easy to hide,"
Harvard University physicist Matthew Bunn says.
- Spent reactor fuel, which cannot be used
directly to make an atomic bomb, is a growing concern among authorities
because it can be processed to extract materials that can be used
for nuclear weapons. The work demands sophisticated skills and equipment,
but it's not the challenge it once was.
The United States "reprocessed" spent
fuel from nuclear reactors for decades to recover plutonium for weapons.
And U.S. scientists have proved recently that other, less-recognized
elements in spent fuel, such as neptunium and americium, also can sustain
the chain reaction needed for nuclear blasts.
Security for spent fuel often is a low priority
because it is seen as too radioactive to handle. But U.S. scientists
have warned for years that poorly guarded spent fuel caches in some
countries have sat for so long that radioactivity has dissipated and
poses less of a risk.
A recently declassified study by Lawrence Livermore
National Laboratory in 1995 found that rogue states or terrorists would
need only "modest facilities and equipment" to extract weapons-ready
nuclear material from spent fuel.
- The amount of nuclear fuel needed to
build a bomb is far less than what is officially stated.
The International Atomic Energy Agency says it takes
17.6 pounds of plutonium or 55.1 pounds of highly enriched uranium —
amounts that could fit in a suitcase — to build a nuclear weapon.
Reactors holding those amounts or more are inspected with greater frequency.
Yet U.S. officials acknowledge that nuclear weapons
can be built using far smaller quantities of those materials.
A 1995 study by the Natural Resources Defense Council
found that terrorists with "low" technical ability could build
a small nuclear weapon with about nine pounds of plutonium or 20 pounds
of highly enriched uranium. A more expert program, such as those run
by Iraq, Iran or North Korea, would need about half those amounts, the
study said. Such a bomb would have about a quarter the power of the
one that destroyed Hiroshima.
"It's a lot easier to make a nuclear explosive
device — and some simple designs require a lot less fissile material
— than the public has been led to believe," says Thomas Cochran,
a physicist who co-authored the study.
New threats perceived
There's debate among U.S. officials over the gravity
of the nuclear threat terrorists or rogue states could pose without
significant amounts of plutonium or highly enriched uranium. In August,
the debate clouded a much-touted mission by U.S., Russian and international
officials to remove more than 100 pounds of highly enriched uranium
from a closed and poorly secured Serbian research reactor. With Serbia's
blessing, the material was taken under heavy guard to a Russian site
where security had been improved with U.S. help.
Officials never revealed in news briefings that
they left behind a cache of spent fuel laced with at least 10 pounds
of plutonium that could be extracted for weapons. The material remains
at the site.
"Some people wanted to take it — there
was a lot of debate," says a U.S. official involved in the mission.
"It would have been a lot of work — more than two tons of
additional material in a lot of containers. But our understanding is
that the plutonium may be concentrated in certain containers, so if
a bad guy got the right ones, he could get some good stuff."
Assessing the risk is tough because officials don't
know what rogue states and terrorists are capable of doing with different
types of nuclear material. U.S. officials worry, for example, that al-Qaeda
picked up nuclear secrets from sympathetic Pakistani scientists.
The other problem is that no one knows how much
nuclear material may be missing around the world. Many research and
power reactors keep shoddy fuel inventories, particularly in former
Soviet states and developing nations. And reports of thefts or losses
tallied by the International Atomic Energy Agency are notoriously spotty.
"No one doubts that there are a number, if
not many, instances of diversion or theft of nuclear material that we're
not aware of," says William Potter, a non-proliferation expert
at the Monterey Institute of International Studies. Many countries don't
disclose losses, he adds, and intelligence sharing is limited.
Data gathered by the International Atomic Energy
Agency and the Monterey Institute reveal several thefts or losses over
the past few years involving low-enriched uranium and small amounts
of traditional weapons fuel.
A daunting set of solutions
Many officials fear they will undermine the critical
mission of securing big stockpiles of plutonium and highly enriched
uranium if they draw attention to the risk posed by lesser grades or
amounts of nuclear material.
Economic woes in the former Soviet states, especially
Russia, have left little money for securing numerous sites storing weapons-ready
nuclear fuel left from the Cold War. U.S. assistance programs to help
consolidate and protect that material have reached fewer than half the
sites of concern.
"We need to have more countries throwing money
into the pot," says Rose Gottemoeller, a former assistant secretary
of Energy now at the Carnegie Endowment for International Peace.
U.S. officials recently won agreement from the seven
other top economic powers to collectively match a U.S. pledge of $10
billion over 10 years for non-proliferation efforts. Meanwhile, many
experts say, safeguards must be tightened.
The rules should reflect that information on making
bombs with low-grade nuclear fuel or small amounts of traditional material
"has leaked out more in recent years," says Laura Holgate
of the Nuclear Threat Initiative, a non-profit group working to curb
the spread of nuclear arms.
Some critics say they expect no action because the
International Atomic Energy Agency's member states fear that their nuclear
industries would be hurt by the costly measures needed to secure all
the types and quantities of nuclear materials that might be useful to
rogue states or terrorists.
Those nations are ignoring the growing capabilities
of those who would steal material for nuclear weapons, says Cochran
of the Natural Resources Defense Council. "They're living in 1945,"