PUBLISHED on August 11, 2025, 12:59 PM EDT – Key Points and Summary – More than a month after U.S. and Israeli strikes, the full extent of the damage to Iran’s nuclear program remains unclear, with intelligence assessments varying widely.
-A new RUSI report argues that the key issue is not just rebuilding, but Iran’s dawning realization that simply possessing a nuclear weapon does not guarantee a credible deterrent.
A United States Air Force B-2 Spirit Bomber from Whiteman Air Force Base, Missouri, undertook a hot pit refueling operation at Lajes Field, on September 12, 2023. The B-2 Spirit Bomber stop at Lajes highlights the readiness and capability of the men and women of the 65th Air Base Group to support global operations when called upon. (U.S. Air Force photo by Cristina Oliveira)
-The attacks exposed the significant limitations of Iran’s “forward defense” strategy and its air defenses.
-Tehran now faces the immense challenge of not only reconstituting its program but also building the vast conventional and delivery systems required for a truly survivable nuclear force.
Iran Needs far More Than Just a Nuclear Bomb
The debate continues as to the degree to which the July attacks by Israel and the US on Iran’s nuclear program have set back—without completely removing—Iran’s capability to develop a nuclear weapon. Iran is reportedly attempting to reconstruct those facilities hit by US Air Force (USAF) B-2 strikes.
But, as a recent long analysis by the Royal United Service Institute (RUSI) in London points out, simply rebuilding the program will not be sufficient for establishing a nuclear deterrent.
Divergent Assessments
More than a month after these attacks on Iran’s underground nuclear development centers and the scientists working there, the full extent of the damage to the Iranian nuclear program is still unclear. Intelligence assessments disagree on the extent of the damage done.
Some of the US and even Israeli intelligence assessments are more reserved than the original assertions that the program had been obliterated.
Pentagon and Israeli estimates are that the program has been set back by as much as two years. Other US intelligence assessments have suggested Iran could start enriching uranium again within months. Regardless of the timelines, the overall important conclusion is that Iran’s program has not been definitively destroyed and could be reconstituted.
The RUSI report concludes that the exact extent of the material damage done to the program is a secondary issue. As other experts have detailed, Iran does not have to reconstitute the entirety of the programme to produce a nuclear weapon. Iran, they say, could, relatively quickly, should it decide to, produce some type of weapon.
The more critical issue is what the impact of the “twelve-day war” is on Iran’s own security assessments and decision-making processes when it comes to the value, as well as the feasibility of, developing a credible nuclear deterrent.
Looking for the Ultimate Deterrent
Recent developments have reinforced incentives for Iran to pursue a nuclear weapon. But the American and Israeli attacks highlighted the ineffectiveness of Iran’s capabilities to deter these kinds of attacks and/or defend against them. Iran has historically relied on a strategy of “forward defence”, employing proxies and allies across the greater Middle East to keep Iran’s enemies away from its borders.
Iran’s missile capabilities were designed to deter attacks on Tehran and other cities and installations and to serve as a means of attacking threats while they are still well away from Iranian territory. That strategy has proved to have very concrete and measurable limitations.
Israel effectively degraded the size and capability of Hamas and Hizbullah, while Iranian missile attacks on Israel proved to be largely unsuccessful. Thus, the limitations of Iran’s “forward defence” strategy have become reasonably clear.
Then there is the failure of Iranian air and missile defence in defending against Israeli and US attacks – both before and during the “twelve-day war” – which has only served to show Iran’s many vulnerabilities.
Iran had been assuming that its possession of a nuclear weapon would be so much of a deterrent as to prevent any attacks of this kind. The US and Israel, they calculated, would be unwilling to risk nuclear retaliation from Iran, so they would never strike. This proved to be a wrong set of assumptions.
Having a nuclear weapon in and of itself, Iran has discovered, is not analogous to having a nuclear deterrent.
An Impossible Task
Tehran is now faced with a serious dilemma on whether to pursue a nuclear weapons capability as a last-ditch effort. Iran most likely lacks the resources to build the number of nuclear warheads, the delivery systems, the means to defend those sites required, as well as to build up the nation’s conventional forces.
All of those assets would need to be in place, and the years it would take to create them would take far longer than it would to just try and assemble a handful of nuclear devices. The incentives for Iran to develop a nuclear weapon are clear, but the associated challenges make just building those nuclear weapons seem a simple task by comparison.
As the RUSI assessment concludes, “Tehran will need to consider whether any nuclear deterrent it can produce will be any more effective than Israel’s has been thus far. The latter neither prevented Hamas from attacking nor dissuaded the Iranians from their missile assault. Although the manner and end to which Iran may employ a nuclear deterrent would probably differ from that of the Israelis, questions over the effectiveness of nuclear deterrence in regional security dynamics remain salient.”
About the Author: Reuben F. Johnson
Reuben F. Johnson has thirty-six years of experience analyzing and reporting on foreign weapons systems, defense technologies, and international arms export policy. Johnson is the Director of Research at the Casimir Pulaski Foundation. He is also a survivor of the Russian invasion of Ukraine in February 2022. He worked for years in the American defense industry as a foreign technology analyst and later as a consultant for the US Department of Defense, the Departments of the Navy and Air Force, and the governments of the United Kingdom and Australia. In 2022-2023, he won two awards in a row for his defense reporting. He holds a bachelor’s degree from DePauw University and a master’s degree from Miami University in Ohio, specializing in Soviet and Russian studies. He lives in Warsaw.
Defense Watch
F/A-XX Is the YF-23 on a Carrier?
bish-bish
August 11, 2025 at 11:54 pm
The weakness is allowing IAEA inspectors back.Iranians should be hurling manure at them !
Iran doesn’t need to develop nukes. As developing nukes require actual testing and other additional mandatory measures like monitoring.
What iran needs is an agreement or agreements with friendly powers to have a share or purchase of miniaturized nuke warheads.
Now, more than ever, all free unencumbered and sovereign nations MUST develop and deploy nuke arsenals to space !!!
It’s crystal clear today the nazist and proto-nazist nations are hellbent on war. All-out war.
For them, their countries are now today getting very massively invaded by migrants from African, Arabian and middle east and south Asian regions, and so the ONLY WAY out is war.
All-out war.