OPINION — “Nuclear facilities on both [the Iranian and Israeli] sides have been targeted. That’s where we are in this war, and that’s how far it’s escalated. If a nuclear reactor like [Iran’s] Bushehr [nuclear power plant] were hit there’s a significant risk of a meltdown and leaks of extremely dangerous radioactive materials that would affect all countries in the [Middle East] region, and, of course millions of people including Americans and American service members.”
That was Rep. Joaquin Castro (D-Texas) speaking last Tuesday at a House Foreign Affairs Committee meeting on “Securing the Future: Arms Control and International Security for the Modern Age,” where Thomas G. DiNanno, Under Secretary of State for Arms Control and International Security was the only witness.
As the U.S./Israeli air attacks have increased and Iranian missile and drone strikes continued, Rep. Castro’s concern was echoed by International Atomic Energy Agency (IAEA) Director General Rafael Mariano Grossi.
At the hearing, Rep. Castro called attention to Iran claiming that on March 17, a projectile hit a structure about 1,000 feet from Iran’s Bushehr nuclear power plant. IAEA’s Grossi called it “the reddest line of nuclear safety.”
On March 21, Iran missiles attacked two southern Israeli cities including Dimona, which is about 8 miles from Israel’s Shimon Peres Negev Nuclear Research Center. This Israeli research center contains a secretive nuclear reactor, plutonium reprocessing facilities, and laboratories -- and was where Israel first developed nuclear weapons in the 1960s.
During last week’s House committee hearing, Castro and DiNanno tangled over Israel’s nuclear weapons program, but I will deal with that below.
Iran’s March 21, ballistic missiles that struck Dimona, injured more than 20 people, but for the first time penetrated Israeli air defenses near what is Israel's main nuclear research facility. Iran said explicitly it was targeting the Negev nuclear research center in retaliation for U.S./Israeli attacks on Iran’s Natanz enrichment facility only a day earlier.
So ten days ago, Iran demonstrated its ability to reach Israel’s most sensitive nuclear-related sites, despite President Trump and Prime Minister Benjamin Netanyahu claiming earlier that Iran’s missile capabilities had been “destroyed.”
On the evening March 24, hours after the above-mentioned House hearing, Iran claimed a U.S. missile struck the premises of the Bushehr Nuclear Power Plant, but there was no damage to the nuclear reactor, no injuries to staff, and the plant continued to operate normally with radiation levels stable. That was the second such attack at Bushehr in just over a week.
A third attack in the vicinity of Bushehr took place last Friday when Israeli planes struck the Shahid Khondab Heavy Water Complex in Arak, a key plutonium production site for possible use in making nuclear weapons. Israel also hit a uranium processing facility in the Iranian city of Yazd, where they extract raw materials essential to the uranium enrichment process. Again, the reports were there were no radiation leaks.
Al Jazeera reported from Tehran that these recent strikes on two major Iranian nuclear-related facilities could prompt the Iran military to target Israeli nuclear sites in Dimona again, as it did on March 21. At the same time, IAEA Director General Grossi reiterated his call for “military restraint to avoid any risk of a nuclear accident."
At the March 24, House hearing, Rep. Castro asked Under Secretary of State for Arms Control DiNanno, “What is the [Trump] administration’s assessment of the risk of nuclear escalation or radiological disaster in this war and what steps is the United States taking to prevent it?”
DiNanno initially replied that “operational questions would rest with [U.S. Central Command’s Commander] Adm. [Charles] Cooper,” and that “all resources that the [State Department] Nonproliferation Bureau [has] would be made available and are available should they want it.”
DiNanno quickly added, “I’ve had conversations with my colleagues in the War Department specifically to this issue and operationally the War Department would address the type of things.”
Asked by Castro if he could share any information he had received, DiNanno replied, “Admiral Cooper would be the decision-maker on how that would be, any hypothetical situation would be, addressed.”
Castro then asked a series of questions about Israel’s nuclear weapons that put DiNanno in a difficult situation, but one that has a complicated history which I will explain below.
Castro said, “I don't believe that you've adequately addressed the nuclear risks here. So, let's take a step back and establish some basic facts. The [Trump] administration has said that Iran is, or was, close to developing nuclear weapons, but they haven't discussed what Israel's capacity or capabilities are. So, I want to ask you, does Israel have nuclear weapons?”
DiNanno answered, “I'm not prepared to comment on that.”
“You’re not prepared to comment on that,” Castro said, and then went on, “It’s a very basic question. We are with an ally, conducting a war against Iran. We all know what American capabilities are; the U.S. Government has spoken what Iran’s capabilities are. Can you tell us what Israel's capabilities are? The consequences, as you know, are grave. This war continues to escalate tell us something as Congress, as the oversight body what is Israel's nuclear capability in terms of weapons?
“I can't comment on that specific question,” DiNanno said, “I'd have to refer you to the Israelis on that.”
“Does that mean you don’t know?” Castro asked.
DiNanno responded, “I can’t comment on that sir.”
I have to point out that Under Secretary DiNanno was following an historic, classified Executive Branch directive which for decades has forced U.S. officials into what’s been called “implausible deniability,” when it comes to the question of Israel’s nuclear weapons arsenal.
Books have been written about how Israel secretly began a nuclear weapons development program in the late 1950s and with the help of some French and American manufacturers by 1967 had built a few nuclear bombs with radioactive material from a nuclear reactor near Dimona.
Aware of the Israeli activity, U.S. Presidents John Kennedy and Lyndon Johnson tried to halt the program but, according to Israeli-American historian Avner Cohen, in 1969 an unwritten agreement was apparently reached between President Richard Nixon and Israeli Prime Minister Golda Meir.
The agreement was that Israel would not confirm it had nuclear weapons nor test any; the U.S. would not push Israel to give them up nor join the Non-Proliferation Treaty. In addition, the U.S. Government adopted as policy that Israel’s possession of nuclear weapons remain a classified secret.
That official U.S. Government policy has continued since 1969, and as a result there is limited public discussion and press coverage of Israel’s nuclear weapons. The Stockholm International Peace Research Institute in 2025 estimated Israel possesses approximately 90 nuclear warheads, but others suggest numbers as high as 200 with nuclear warheads on ballistic and cruise missiles and well as nuclear bombs.
Nonetheless, there is coverage not just in the American press, but also in the Israeli press.
For example, back in June 2002, I wrote in The Washington Post a story that began, “Israel has acquired three diesel submarines that it is arming with newly designed cruise missiles capable of carrying nuclear warheads, according to former Pentagon and State Department officials, potentially giving Israel a triad of land-, sea- and air-based nuclear weapons for the first time.”
In 2016, the Times of Israel, using a standard attribution “according to foreign reports” as a way of not violating their country’s secrecy, described those same Israeli submarines as “capable of delivering a nuclear payload.”
One reason Iran’s hardliners want a nuclear weapon is because Israel, their nearby neighbor, has had them for decades.
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