Iran
has now produced roughly enough nuclear material to make, with added
purification, a single atom bomb, according to nuclear experts
analyzing the latest report from global atomic inspectors.
The
figures detailing Iran's progress were contained in a routine update on
Wednesday from the International Atomic Energy Agency, which has been
conducting inspections of the country's main nuclear plant at Natanz.
The report concluded that as of early this month, Iran had made 630
kilograms, or about 1,390 pounds, of low-enriched uranium.
Several
experts said that was enough for a bomb, but they cautioned that the
milestone was mostly symbolic, because Iran would have to take
additional steps. Not only would it have to breach its international
agreements and kick out the inspectors, but it would also have to
further purify the fuel and put it into a warhead design — a technical
advance that Western experts are unsure Iran has yet achieved.
"They
clearly have enough material for a bomb," said Richard Garwin, a top
nuclear physicist who helped invent the hydrogen bomb and has advised
Washington for decades. "They know how to do the enrichment. Whether
they know how to design a bomb, well, that's another matter."
Iran
insists that it wants only to fuel reactors for nuclear power. But many
Western nations, led by the United States, suspect that its real goal
is to gain the ability to make nuclear weapons.
While some Iranian officials have threatened
to bar inspectors in the past, the country has made no such moves, and
many experts inside the Bush administration and the IAEA believe it
will avoid the risk of attempting "nuclear breakout" until it possessed
a larger uranium supply.
Even so, for President-elect Barack
Obama, the report underscores the magnitude of the problem that he will
inherit Jan. 20: an Iranian nuclear program that has not only solved
many technical problems of uranium enrichment, but that can also now
credibly claim to possess enough material to make a weapon if
negotiations with Europe and the United States break down.
American
intelligence agencies have said Iran could make a bomb between 2009 and
2015. A national intelligence estimate made public late last year
concluded that around the end of 2003, after long effort, Iran had
halted work on an actual weapon. But enriching uranium, and obtaining
enough material to build a weapon, is considered the most difficult
part of the process.
Siegfried Hecker of Stanford University
and a former director of the Los Alamos weapons laboratory said the
growing size of the Iranian stockpile "underscored that they are
marching down the path to developing the nuclear weapons option."
In
the report to its board, the atomic agency said Iran's main enrichment
plant was now feeding uranium into about 3,800 centrifuges — machines
that spin incredibly fast to enrich the element into nuclear fuel. That
count is the same as in the agency's last quarterly report, in
September. Iran began installing the centrifuges in early 2007. But the
new report's total of 630 kilograms — an increase of about 150 — shows
that Iran has been making progress in accumulating material to make
nuclear fuel.
That uranium has been enriched to the low
levels needed to fuel a nuclear reactor. To further purify it to the
highly enriched state needed to fuel a nuclear warhead, Iran would have
to reconfigure its centrifuges and do a couple months of additional
processing, nuclear experts said.
"They have a weapon's
worth," Thomas Cochran, a senior scientist in the nuclear program of
the Natural Resources Defense Council, a private group in Washington
that tracks atomic arsenals, said in an interview.
He said
the amount was suitable for a relatively advanced implosion-type weapon
like the one dropped on Nagasaki. Its core, he added, would be about
the size of a grapefruit. He said a cruder design would require about
twice as much weapon-grade fuel.
"It's a virtual milestone,"
Cochran said of Iran's stockpile. It is not an imminent threat, he
added, because the further technical work to make fuel for a bomb would
tip off inspectors, the United States and other powers about "where
they're going."
The agency's report made no mention of the
possible military implications of the size of Iran's stockpile. And
some experts said the milestone was still months away. In an analysis
of the IAEA report, the Institute for Science and International
Security, a private group in Washington, estimated that Iran had not
yet reached the mark but would "within a few months." It added that
other analysts estimated it might take as much as a year.