Trump's reported consideration of a nuclear option comes amid internal concerns that the 30,000-pound bunker-buster bombs the U.S. possesses within striking distance of Iran would be insufficient to destroy Fordow. The massive bombs have never been used in active combat.
Trump is expected to decide whether to join nuclear-armed Israel's assault on Iran "within two weeks," White House Press Secretary Karoline Leavitt told reporters Thursday, reading a message that she described as coming directly from the president. Trump denied a Wednesday Wall Street Journalstory suggesting that he had already approved a plan to attack Iran.
Use of a nuclear weapon against Iran in a purported effort to stop the country from developing a nuke of its own—despite U.S. intelligence indicating that Iran's leadership has not decided to pursue one—would be catastrophic, according to experts and opponents of American intervention in the conflict.
Hans Kristensen, director of the Nuclear Information Project at the Federation of American Scientists, warned that "radioactive fallout would be intense" if the U.S. deployed a B61-11 penetrator nuke.
Jeffrey Lewis, a professor at the Middlebury Institute, echoed that concern:
Eli Clifton, a senior adviser at the Quincy Institute for Responsible Statecraft, expressed astonishment at the Trump White House's position.
"The U.S. is considering using a nuclear weapon for the first time since Hiroshima and Nagasaki because our client state murdered our Iranian negotiating partner and started a war?" Clifton asked.
News that the White House has not ruled out a nuclear attack on Iran also drew the attention of Russia, which has the world's largest nuclear arsenal.
"There have been a lot of speculations," Kremlin spokesman Dmitry Peskov said Friday. "This would be a catastrophic development, but there are so many speculations that in fact, it's impossible to comment on them."
While the White House stressed that all options are on the table regarding military action in Iran, Leavitt said Thursday that Trump believes there is a "chance for substantial negotiations."
Anti-war campaigners interpreted that message as evidence that the growing pressure campaign against a military attack is having an impact.
"The anti-war movement is working," said the advocacy group Demand Progress. "There are Iran war powers votes coming up in Congress soon. Time to keep the pressure up. Use our tool at 1833STOPWAR (dot) com or call 1-833-STOP-WAR to connect with offices after entering your zip code."
Leavitt on Thursday dodged a reporter's question on whether Trump would seek congressional approval for a U.S. strike on Iran.
Jennifer Kavanagh, director of military analysis at the think tank Defense Priorities, said in a statement Thursday that "the notion that the United States can conduct a few airstrikes and declare victory is an illusion."
"Any direct U.S. military strike on Iran is likely to mission creep into regime change or collapse or spiral into a long, protracted war," Kavanagh warned. "Israel's strikes on Iran may make U.S. diplomatic efforts more difficult, but there is still a chance at a deal—and plenty of time to pursue one through negotiations."
Iraqis protest Israel's strikes on Iran, following the weekly Friday noon prayers in Baghdad's Sadr City on June 20, 2025. (Photo: Murtadha Ridha/AFP via Getty Images)