• The Smaller Bombs That Could Turn Ukraine into a Nuclear War Zone

    The nuclear weapons in the arsenals of Russia and NATO countries have much smaller yields than the large bombs built during the Cold War. These warheads are even smaller than the bombs dropped on Hiroshima and Nagasaki. William Broad writes that it is this much lower yield which makes their use more thinkable.

  • Israel-Iran Stealthy War Intensifies

    Last Sunday, Iran launched a missile attack which destroyed an Israeli intelligence facility located in Irbil, in the Kurdish autonomous zone in Iraq. The Iranian attack was in retaliation for a daring, and successful, mid-February Israeli attack, using six armed drones, on an Iranian drone production facility, in which hundreds of advanced Iranian drones were destroyed. Israel operates several intelligence and military bases in the Kurdish region and in Azerbaijan.

  • U.S. Mulls Iran’s Bomb-Making Scenarios Iran Nears Uranium Breakout Capacity

    With the United States warning that Iran is just weeks from developing the capacity to make a nuclear weapon, there is disagreement among Washington experts on the likelihood of Iran rushing to build such a weapon, and how the U.S. and its allies should deal with that risk.

  • Examining How Countries Go Nuclear — and Why Some Do Not

    In a new book, political scientist Vipin Narang argues that too often we imagine that all countries pursue nuclear weapons the way the U.S. and Soviet Union did during and after World War II — a swift race culminating in the rapid buildup of arsenals, leaving little room for intervention. But that paradigm applies to almost no other country. Recognizing how different countries choose different paths to proliferation is an essential part of arms control: Grasping how one country is pursuing nuclear weapons can help other countries constrain that pursuit.

  • The Progress of Iran’s Nuclear Weapons Program

    As of November 2021, Iran had enough enriched uranium hexafluoride (UF6) in the form of near 20 and 60 percent enriched uranium to produce enough weapon-grade uranium (WGU), taken here as 25 kilograms, for a single nuclear weapon in as little as three weeks. It could do so without using any of its stock of uranium enriched up to 5 percent as feedstock. The growth of Iran’s stocks of near 20 and 60 percent enriched uranium has dangerously reduced breakout timelines.

  • China’s Nuclear Buildup is About More Than Nukes

    U.S.-China nuclear and strategic stability will be tested in the coming year after a series of revelations in 2021 about Beijing’s nuclear program. Jacob Stokes writes that “The U.S.-China nuclear and strategic relationship has entered a new stage.” He adds: “Pursuing nuclear and strategic stability between the United States and China will likely prove harder than ever — but it is perhaps more important than ever, too.”

  • U.S.: Iran's Nuclear Breakout Time “Really Short”

    An unnamed source within the Biden administration has said that the amount of time required for Iran to develop nuclear weapons if it chooses to do so is “really short,” adding that the situation was “alarming.”

  • Iran Can Produce One Nuclear Weapon in as Little as Three Weeks

    The growth of Iran’s stocks of near 20 and 60 percent enriched uranium has dangerously reduced breakout timelines: Iran has enough enriched uranium hexafluoride (UF6) in the form of near 20 and 60 percent enriched uranium to produce enough weapon-grade uranium (WGU), taken here as 25 kilograms (kg), for a single nuclear weapon in as little as three weeks. It could do so without using any of its stock of uranium enriched up to 5 percent as feedstock.

  • China Nuclear Arsenal Growing Faster Than Previously Thought: Pentagon

    The Pentagon warns that China’s rapidly growing nuclear arsenal is expanding at a much faster pace than estimated just a year ago, while a new Chinese military modernization goal could provide Beijing with “more credible military operations in Taiwan.”

  • U.S. Iran Envoy: Tehran May Be Delaying Talks to Advance Nuclear Program

    Rob Malley, the top U.S. envoy on Iran says talks to revive the moribund the 2015 nuclear deal between Tehran and world powers are at a “critical phase,” warning that Iran may be engaging in delaying tactics to advance its nuclear program.

  • Nuclear War's Smoke Would Cause Climate Change, Threatening Global Food Supplies

    Nuclear war would cause many immediate fatalities, but smoke and soot from the resulting fires would also cause climate change lasting up to fifteen years, threatening worldwide food production and human health, according to a new study.

  • Quick Detection of Uranium Isotopes Helps Safeguard Nuclear Materials

    Researchers have developed a rapid way to measure isotopic ratios of uranium and plutonium collected on environmental swipes, which could help International Atomic Energy Agency analysts detect the presence of undeclared nuclear activities or material.

  • U.S. Has a Stockpile of 3,750 Nuclear Warheads

    The United States has disclosed the number of nuclear weapons in its arsenal for the first time since former President Donald Trump decided to keep the figures a secret. At the height of the cold war, in 1967, the U.S. nuclear stockpile reached its peak; 31,255 warheads.

  • Bolstering Speed, Flexibility of Response to Nuclear Events

    Researchers are combining basic research and development of emergent technologies, predictive capabilities, and systems assessment to revolutionize the speed and flexibility of technical nuclear forensic (TNF) response to nuclear events.

  • IAEA: Iran Denying Monitoring Access at “Indispensable” Site

    The IAEA, the UN nuclear watchdog, says Iran has not allowed international inspectors access to a centrifuge-component-manufacturing workshop as agreed under a monitoring deal reached two weeks ago.