[Mr. Obama, according to participants in the many Situation Room meetings on Olympic Games, was acutely aware that with every attack he was pushing the United States into new territory, much as his predecessors had with the first use of atomic weapons in the 1940s, of intercontinental missiles in the 1950s and of drones in the past decade. He repeatedly expressed concerns that any American acknowledgment that it was using cyberweapons — even under the most careful and limited circumstances — could enable other countries, terrorists or hackers to justify their own attacks.]
By David E. Sanger
Hasan Sarbakhshian/Associated Press |
Mr. Obama decided to accelerate the attacks — begun in the
Bush administration and code-named Olympic Games — even after an element of the
program accidentally became public in the summer of 2010 because of a
programming error that allowed it to escape Iran’s Natanz plant and sent it
around the world on the Internet. Computer security experts who began studying
the worm, which had been developed by the United States and Israel , gave it a name: Stuxnet.
At a tense meeting in the White House Situation Room within
days of the worm’s “escape,” Mr. Obama, Vice President Joseph R. Biden Jr. and
the director of the Central
Intelligence Agency at
the time, Leon E. Panetta, considered whether America’s most ambitious attempt
to slow the progress of Iran’s nuclear efforts had been fatally compromised.
“Should we shut this thing down?” Mr. Obama asked,
according to members of the president’s national security team who were in the
room.
Told it was unclear how much the Iranians knew about the
code, and offered evidence that it was still causing havoc, Mr. Obama decided
that the cyberattacks should proceed. In the following weeks, the Natanz plant
was hit by a newer version of the computer worm, and then another after that.
The last of that series of attacks, a few weeks after Stuxnet was detected
around the world, temporarily took out nearly 1,000 of the 5,000 centrifuges
Iran had spinning at the time to purify uranium.
This account of the American and Israeli effort to
undermine the Iranian nuclear program is based on interviews over the past
18 months with current and former American, European and Israeli officials
involved in the program, as well as a range of outside experts. None would
allow their names to be used because the effort remains highly classified, and
parts of it continue to this day.
These officials gave differing assessments of how
successful the sabotage program was in slowing Iran ’s progress toward developing the ability to build nuclear weapons. Internal
Obama administration estimates say the effort was set back by 18 months to two
years, but some experts inside and outside the government are more skeptical,
noting that Iran’s enrichment levels have steadily recovered, giving the
country enough fuel today for five or more weapons, with additional enrichment.
Whether Iran is still trying to design and build a weapon is in
dispute. The most recent United States intelligence estimate concludes that Iran suspended major parts of its weaponization effort after
2003, though there is evidence that some remnants of it continue.
The United States government only recently acknowledged developing
cyberweapons, and it has never admitted using them. There have been reports of
one-time attacks against personal computers used by members of Al Qaeda, and of
contemplated attacks against the computers that run air defense systems,
including during the NATO-led air attack on Libya last year. But Olympic Games was of an entirely different
type and sophistication.
It appears to be the first time the United States has repeatedly used cyberweapons to cripple another
country’s infrastructure, achieving, with computer code, what until then could
be accomplished only by bombing a country or sending in agents to plant
explosives. The code itself is 50 times as big as the typical computer worm,
Carey Nachenberg, a vice president of Symantec, one of the many groups that
have dissected the code, said at a symposium at Stanford
University in April. Those forensic investigations into the inner
workings of the code, while picking apart how it worked, came to no conclusions
about who was responsible.
A similar process is now under way to figure out the
origins of another cyberweapon called Flame that was recently discovered to have
attacked the computers of Iranian officials, sweeping up information from those
machines. But the computer code appears to be at least five years old, and
American officials say that it was not part of Olympic Games. They have
declined to say whether the United States was responsible for the Flame attack.
Mr. Obama, according to participants in the many Situation
Room meetings on Olympic Games, was acutely aware that with every attack he was
pushing the United
States into
new territory, much as his predecessors had with the first use of atomic
weapons in the 1940s, of intercontinental missiles in the 1950s and of drones
in the past decade. He repeatedly expressed concerns that any American
acknowledgment that it was using cyberweapons — even under the most careful and
limited circumstances — could enable other countries, terrorists or hackers to
justify their own attacks.
“We discussed the irony, more than once,” one of his aides
said. Another said that the administration was resistant to developing a “grand
theory for a weapon whose possibilities they were still discovering.” Yet Mr.
Obama concluded that when it came to stopping Iran , the United States had no other choice.
If Olympic Games failed, he told aides, there would be no
time for sanctions and diplomacy with Iran to work. Israel could carry out a conventional military attack, prompting
a conflict that could spread throughout the region.
A Bush Initiative
The impetus for Olympic Games dates from 2006, when
President George W. Bush saw few good options in dealing with Iran . At the time, America ’s European allies were divided about the cost that
imposing sanctions on Iran would have on their own economies. Having falsely accused
Saddam Hussein of reconstituting his nuclear program in Iraq , Mr. Bush had little credibility in publicly discussing
another nation’s nuclear ambitions. The Iranians seemed to sense his
vulnerability, and, frustrated by negotiations, they resumed enriching uranium
at an underground site at Natanz, one whose existence had been exposed just
three years before.
Hawks in the Bush administration like Vice President Dick
Cheney urged Mr. Bush to consider a military strike against the Iranian nuclear
facilities before they could produce fuel suitable for a weapon. Several times,
the administration reviewed military options and concluded that they would only
further inflame a region already at war, and would have uncertain results.
For years the C.I.A. had introduced faulty parts and
designs into Iran’s systems — even tinkering with imported power supplies so
that they would blow up — but the sabotage had had relatively little effect.
General James E. Cartwright, who had established a small cyberoperation inside
the United States Strategic Command, which is responsible for many of America ’s nuclear forces, joined intelligence officials in
presenting a radical new idea to Mr. Bush and his national security team. It
involved a far more sophisticated cyberweapon than the United States had designed before.
The goal was to gain access to the Natanz plant’s
industrial computer controls. That required leaping the electronic moat that
cut the Natanz plant off from the Internet — called the air gap, because it
physically separates the facility from the outside world. The computer code
would invade the specialized computers that command the centrifuges.
The first stage in the effort was to develop a bit of
computer code called a beacon that could be inserted into the computers, which
were made by the German company Siemens and an Iranian manufacturer, to map
their operations. The idea was to draw the equivalent of an electrical
blueprint of the Natanz plant, to understand how the computers control the
giant silvery centrifuges that spin at tremendous speeds. The connections were
complex, and unless every circuit was understood, efforts to seize control of
the centrifuges could fail.
Eventually the beacon would have to “phone home” —
literally send a message back to the headquarters of the National Security
Agency that would describe the structure and daily rhythms of the enrichment
plant. Expectations for the plan were low; one participant said the goal was
simply to “throw a little sand in the gears” and buy some time. Mr. Bush was
skeptical, but lacking other options, he authorized the effort.
Breakthrough, Aided by Israel
It took months for the beacons to do their work and report
home, complete with maps of the electronic directories of the controllers and
what amounted to blueprints of how they were connected to the centrifuges deep
underground.
Then the N.S.A. and a secret Israeli unit respected by
American intelligence officials for its cyberskills set to work developing the
enormously complex computer worm that would become the attacker from within.
The unusually tight collaboration with Israel was driven by two imperatives. Israel ’s Unit 8200, a part of its military, had technical
expertise that rivaled the N.S.A.’s, and the Israelis had deep intelligence
about operations at Natanz that would be vital to making the cyberattack a
success. But American officials had another interest, to dissuade the Israelis
from carrying out their own pre-emptive strike against the Iranian nuclear
facilities. To do that, the Israelis would have to be convinced that the new
line of attack was working. The only way to convince them, several officials
said in interviews, was to have them deeply involved in every aspect of the
program.
Soon the two countries had developed a complex worm that
the Americans called “the bug.” But the bug needed to be tested. So, under
enormous secrecy, the United States began building replicas of Iran ’s P-1 centrifuges, an aging, unreliable design that Iran purchased from Abdul Qadeer Khan, the Pakistani nuclear
chief who had begun selling fuel-making technology on the black market.
Fortunately for the United States , it already owned some P-1s, thanks to the Libyan
dictator, Col. Muammar el-Qaddafi.
When Colonel Qaddafi gave up his nuclear weapons program in
2003, he turned over the centrifuges he had bought from the Pakistani nuclear
ring, and they were placed in storage at a weapons laboratory in Tennessee . The military and intelligence officials overseeing
Olympic Games borrowed some for what they termed “destructive testing,”
essentially building a virtual replica of Natanz, but spreading the test over
several of the Energy Department’s national laboratories to keep even the most
trusted nuclear workers from figuring out what was afoot.
Those first small-scale tests were surprisingly successful:
the bug invaded the computers, lurking for days or weeks, before sending
instructions to speed them up or slow them down so suddenly that their delicate
parts, spinning at supersonic speeds, self-destructed. After several false
starts, it worked. One day, toward the end of Mr. Bush’s term, the rubble of a
centrifuge was spread out on the conference table in the Situation Room, proof
of the potential power of a cyberweapon. The worm was declared ready to test
against the real target: Iran ’s underground enrichment plant.
“Previous cyberattacks had effects limited to other computers,”
Michael V. Hayden, the former chief of the C.I.A., said, declining to describe
what he knew of these attacks when he was in office. “This is the first attack
of a major nature in which a cyberattack was used to effect physical
destruction,” rather than just slow another computer, or hack into it to steal
data.
“Somebody crossed the Rubicon,” he said.
Getting the worm into Natanz, however, was no easy trick.
The United
States and Israel would have to rely on engineers, maintenance workers and
others — both spies and unwitting accomplices — with physical access to the
plant. “That was our holy grail,” one of the architects of the plan said. “It
turns out there is always an idiot around who doesn’t think much about the
thumb drive in their hand.”
In fact, thumb drives turned out to be critical in
spreading the first variants of the computer worm; later, more sophisticated
methods were developed to deliver the malicious code.
The first attacks were small, and when the centrifuges
began spinning out of control in 2008, the Iranians were mystified about the
cause, according to intercepts that the United States later picked up. “The thinking was that the Iranians would
blame bad parts, or bad engineering, or just incompetence,” one of the
architects of the early attack said.
The Iranians were confused partly because no two attacks
were exactly alike. Moreover, the code would lurk inside the plant for weeks,
recording normal operations; when it attacked, it sent signals to the Natanz
control room indicating that everything downstairs was operating normally.
“This may have been the most brilliant part of the code,” one American official
said.
Later, word circulated through the International Atomic
Energy Agency, the Vienna-based nuclear watchdog, that the Iranians had grown
so distrustful of their own instruments that they had assigned people to sit in
the plant and radio back what they saw.
“The intent was that the failures should make them feel
they were stupid, which is what happened,” the participant in the attacks said.
When a few centrifuges failed, the Iranians would close down whole “stands”
that linked 164 machines, looking for signs of sabotage in all of them. “They
overreacted,” one official said. “We soon discovered they fired people.”
Imagery recovered by nuclear inspectors from cameras at
Natanz — which the nuclear agency uses to keep track of what happens between
visits — showed the results. There was some evidence of wreckage, but it was
clear that the Iranians had also carted away centrifuges that had previously
appeared to be working well.
But by the time Mr. Bush left office, no wholesale
destruction had been accomplished. Meeting with Mr. Obama in the White House
days before his inauguration, Mr. Bush urged him to preserve two classified
programs, Olympic Games and the drone program in Pakistan . Mr. Obama took Mr. Bush’s advice.
The Stuxnet Surprise
Mr. Obama came to office with an interest in cyberissues,
but he had discussed them during the campaign mostly in terms of threats to
personal privacy and the risks to infrastructure like the electrical grid and
the air traffic control system. He commissioned a major study on how to improve
America ’s defenses and announced it with great fanfare in the East
Room.
What he did not say then was that he was also learning the
arts of cyberwar. The architects
of Olympic Games would meet him in the Situation Room, often with what they
called the “horse blanket,” a giant foldout schematic diagram of Iran ’s nuclear production facilities. Mr. Obama authorized the
attacks to continue, and every few weeks — certainly after a major attack — he
would get updates and authorize the next step. Sometimes it was a strike
riskier and bolder than what had been tried previously.
“From his first days in office, he was deep into every step
in slowing the Iranian program — the diplomacy, the sanctions, every major
decision,” a senior administration official said. “And it’s safe to say that
whatever other activity might have been under way was no exception to that
rule.”
But the good luck did not last. In the summer of 2010,
shortly after a new variant of the worm had been sent into Natanz, it became
clear that the worm, which was never supposed to leave the Natanz machines, had
broken free, like a zoo animal that found the keys to the cage. It fell to Mr.
Panetta and two other crucial players in Olympic Games — General Cartwright,
the vice chairman of the Joint Chiefs of Staff, and Michael J. Morell, the
deputy director of the C.I.A. — to break the news to Mr. Obama and Mr. Biden.
An error in the code, they said, had led it to spread to an
engineer’s computer when it was hooked up to the centrifuges. When the engineer
left Natanz and connected the computer to the Internet, the American- and
Israeli-made bug failed to recognize that its environment had changed. It began
replicating itself all around the world. Suddenly, the code was exposed, though
its intent would not be clear, at least to ordinary computer users.
“We think there was a modification done by the Israelis,”
one of the briefers told the president, “and we don’t know if we were part of
that activity.”
Mr. Obama, according to officials in the room, asked a
series of questions, fearful that the code could do damage outside the plant.
The answers came back in hedged terms. Mr. Biden fumed. “It’s got to be the
Israelis,” he said. “They went too far.”
In fact, both the Israelis and the Americans had been
aiming for a particular part of the centrifuge plant, a critical area whose
loss, they had concluded, would set the Iranians back considerably. It is
unclear who introduced the programming error.
The question facing Mr. Obama was whether the rest of
Olympic Games was in jeopardy, now that a variant of the bug was replicating
itself “in the wild,” where computer security experts can dissect it and figure
out its purpose.
“I don’t think we have enough information,” Mr. Obama told
the group that day, according to the officials. But in the meantime, he ordered
that the cyberattacks continue. They were his best hope of disrupting the
Iranian nuclear program unless economic sanctions began to bite harder and
reduced Iran ’s oil revenues.
Within a week, another version of the bug brought down just
under 1,000 centrifuges. Olympic Games was still on.
A Weapon’s Uncertain Future
American cyberattacks are not limited to Iran , but the focus of attention, as one administration
official put it, “has been overwhelmingly on one country.” There is no reason
to believe that will remain the case for long. Some officials question why the
same techniques have not been used more aggressively against North Korea . Others see chances to disrupt Chinese military plans,
forces in Syria on the way to suppress the uprising there, and Qaeda
operations around the world. “We’ve considered a lot more attacks than we have
gone ahead with,” one former intelligence official said.
Mr. Obama has repeatedly told his aides that there are
risks to using — and particularly to overusing — the weapon. In fact, no
country’s infrastructure is more dependent on computer systems, and thus more
vulnerable to attack, than that of the United States . It is only a matter of time, most experts believe, before
it becomes the target of the same kind of weapon that the Americans have used,
secretly, against Iran .