Ask PolitiFact: Was Iran ‘weeks away’ from having a nuclear weapon, as Trump said?

Days before the United States’ June 21 strike on three Iran nuclear sites, President Donald Trump said the country was "weeks away" from having a nuclear weapon. 

On its face, Trump’s comment seemed to contradict March remarks from Director of National Intelligence Tulsi Gabbard.

At a Senate hearing, Gabbard said the intelligence community "continues to assess that Iran is not building a nuclear weapon and Supreme Leader Khamenei has not authorized the nuclear weapons program that he suspended in 2003." 

But Gabbard also warned that "Iran's enriched uranium stockpile is at its highest levels and is unprecedented for a state without nuclear weapons." Enriched uranium is the first step in building a nuclear bomb, which also requires a delivery vehicle such as a ballistic missile. 

Brendan Green, a University of Cincinnati associate professor and expert on nuclear strategy, said Trump’s and Gabbard’s comments are not at odds.

"The (intelligence community) is saying: We do not believe Iran has made a decision to weaponize its highly enriched uranium stocks," Green said. "The President is saying: If Iran decided to weaponize, it could do so fairly rapidly, given its current (highly enriched uranium) stocks."

While Iran was close to having the enriched uranium to the level needed for bomb-making, experts said it would take months to two years to build a nuclear bomb. How quickly Iran could possess a nuclear weapon was used as the basis for Israel and the U.S. to strike.

Iran didn’t yet have a bomb ready to launch, said Michael Singh, managing director at The Washington Institute for Near East Policy, an organization that promotes understanding of American interests in the Middle East.

Although having bomb-grade uranium is "only one step in having a bomb ready to launch, it is a vital one because once Iran produced the enriched uranium, it could transport it and hide it, making it difficult to detect further steps toward producing a weapon," Singh said. He worked as a special assistant to secretaries of state Condoleezza Rice and Colin Powell.

Shawn Rostker, a research analyst at the Center for Arms Control and Non-Proliferation, said uranium enrichment is one part of the process, "but building a nuclear weapon requires additional steps like warhead design and delivery system integration."

RELATED: Did Trump violate War Powers Act by bombing Iran nuclear sites?

Trump’s remarks about weapons intelligence

On June 20, a reporter asked Trump, "What intelligence do you have that Iran is building a nuclear weapon? Your intelligence community has said they have no evidence that they are at this point."

Trump said: "Well, then my intelligence community is wrong. Who in the intelligence community said that?"

The reporter said: "Your Director of National Intelligence, Tulsi Gabbard."

Trump said: "She's wrong." 

Others in the Trump administration, including Vance, defended Gabbard. 

Singh said, "Both the president saying Iran was only weeks away from a bomb and (the director of national intelligence) saying we see no decision or indication they are making weapons could both be true. They had the capability to make fuel for a weapon if they wanted to, we just don't know if they had made that decision. Both are correct, but both when spoken convey a very different picture of the urgency."

On June 10, U.S. Army Gen. Michael "Erik" Kurilla with U.S. Central Command said in a statement that should Iran "decide to sprint to a nuclear weapon," its stockpiles and centrifuges were sufficient to produce first weapons grade material in roughly one week and "up to ten nuclear weapons in three weeks."

Iran close to enriching uranium further, but timeline for a bomb less certain 

Trump and officials in his administration have repeated the "weeks away" timeframe several times. 

A reporter asked White House spokesperson Karoline Leavitt on June 19 if Trump meant Iran was weeks away from "obtaining enough enriched uranium to start building a weapon" or "from completing the production of a weapon?"

"Iran has all that it needs to achieve a nuclear weapon — all they need is a decision from the Supreme leader to do that, and it would take a couple of weeks to complete the production of that weapon," Leavitt said. She also said June 23 on "Fox and Friends," "Based on U.S. intelligence, that Iran is just weeks away from obtaining a nuclear weapon."

Hans M. Kristensen, an expert on nuclear weapons at the Federation of American Scientists, said one timeline is about bomb-grade uranium, and the timeline for producing that is days to a week, or perhaps several months. 

Another timeline is about finishing development of a warhead design that could use the fissile material, and that could take several months, Kristensen said.

"In total, there are several hurdles that have to be overcome before Iran could use a functioning nuclear weapon," Kristensen said.

The U.S. intelligence community said for more than a year that Iran was weeks away from enriching uranium further to bomb grade, said Daryl Kimball, executive director of the Arms Control Association. 

"That is extremely worrisome but that is not weeks away from having a nuclear weapon and not weeks away from having a nuclear weapon that can be loaded on a nuclear missile," Kimball said.

It is one thing to have raw material but it is another thing to fashion into a nuclear device that can be loaded on a truck, transported and be small enough and light enough to be launched by a ballistic missile as a nuclear weapon.

"My understanding from non-governmental sources and the internal assessment of the (intelligence community) is that they believe it would take several months or more to fashion the highly enriched uranium bomb grade into a nuclear device, and one to two years to manufacture a small light nuclear device," Kimball said.

Once Iran has that uranium, it has been a matter of debate as to how long it would take Iran to complete the steps to build a bomb that it could launch with experts generally citing timelines between six months and two years, Singh said. But in recent years, some experts have indicated a shorter time frame.

The different Iran nuclear timeline estimates that experts predict could be a result of having different access to intelligence information, Singh said. And that intelligence is highly technical.

 "You have to both have the information and understand the information to come up with informed judgment," Singh said. 

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