Israel and the United States recently revised their estimates of when Iran will field a nuclear weapon, reflecting difficulties inside Tehran’s program of building large numbers of centrifuges to enrich uranium.
Israel’s former civilian intelligence chief, Meir Dagan, told Israeli newspapers last weekend that he thought Iran will not be able to produce an atomic bomb until 2015. The interview is significant in part because Mr. Dagan, who recently left the post, has made Iran a major focus for the Mossad intelligence service since he took over in 2002.
Mr. Dagan’s estimates also coincide with recent U.S. intelligence community analysis that states Iran has run into difficulties in acquiring the refined equipment it needs to produce more centrifuges and to run the machines properly.
A new U.S. national intelligence estimate for Iran has been stalled for nearly a year, but U.S. officials familiar with the estimate say they expect a new classified estimate to be released as soon as this month.
Iran’s difficulties also are likely to be the result of a covert Israeli program of sabotage and U.S. efforts against the country’s nuclear program.
A powerful computer virus known as Stuxnet reportedly attacked Iran’s nuclear facilities earlier this year. Since then, Iran’s president, Mahmoud Ahmadinejad, has spoken publicly about computer problems the nuclear program has experienced.
In November, Iran’s president said, “they succeeded in creating problems for a limited number of our centrifuges with the software they had installed in electronic parts.”
No country has claimed credit for launching the sophisticated Stuxnet computer virus that reportedly varies the speeds of the delicate high-speed centrifuges, speeding them up and slowing them down so they are rendered useless.
The Internet site WikiLeaks disclosed last month a State Department cable confirming that Israel has waged a covert war against Iran’s nuclear program under Mr. Dagan.
The cable, which recounted a Aug. 17, 2007, meeting between Undersecretary of State Nicholas Burns and Mr. Dagan said the Israeli spy chief outlined Israel’s five-pillar strategy for preventing Iran from becoming a nuclear power.
Those five pillars included both something the memo called “covert measures” and “force regime change,” or support for elements of Iran’s opposition.
In the meeting, Mr. Dagan said, the United States and Israel had different estimated timelines for when Iran would acquire a nuclear weapon. “The threat is obvious, even if we have a different timetable,” the cable quotes Mr. Dagan as saying.
A recent analysis of the Stuxnet virus by the U.S.-based Institute for Science and International Security estimated that the virus had been sent as early as 2009.
The paper noted that Iran replaced 1,000 centrifuges at the Natanz facility in late 2009 or early 2010. The paper also quoted Ali Akbar Salehi, then the head of Iran’s Atomic Energy Organization and currently the country’s foreign minister, as saying in a November interview that Westerners had sent a computer virus to Iran’s nuclear program “one year and several months ago.”
Patrick Clawson, a specialist at the Washington Institute for Near East Policy, said: “Certainly, the IAEA reports and what we hear from people knowledgeable about the nuclear program is that Iran is encountering significant technical problems.”
“The great worry is that Iran has clandestine facilities that will allow it to overcome these technical problems,” he said.
Mr. Clawson noted that he was also worried that Iran could still gain nuclear fuel because of its ties to North Korea, which has tested a nuclear device already.