Updated Feb. 28, 2026 — Washington
President Trump ordered U.S. military strikes on Iran early Saturday after months of pressure over Tehran’s nuclear activities, which have long been a source of U.S. and international concern. Iran, which denies seeking nuclear weapons, has built up a large stockpile of highly enriched uranium. The president said the strikes follow repeated failed attempts to reach a diplomatic solution and described the campaign as a “massive and ongoing operation.”
How close is Iran to building a nuclear weapon, and is it doing so now?
IAEA figures show Iran dramatically increased its inventory of uranium enriched to about 60% purity in recent years. As of mid‑June 2025 — just before U.S. strikes that month — the agency reported roughly 972 pounds of uranium at about 60% enrichment. That compares with about 605.8 pounds reported in February 2025 and 267.9 pounds in early 2024. Experts say roughly 92.5 pounds of 60%‑enriched uranium, if further enriched, would be enough material for a single nuclear device.
Sixty percent enrichment is a relatively short technical step from weapons‑grade material (around 90% enrichment). In May, the U.S. Defense Intelligence Agency estimated Iran could likely produce enough weapons‑grade uranium for a first bomb “probably less than one week” if it chose to rush the process. A separate U.S. intelligence assessment last year put a potential timetable for building a device, absent delays, at roughly three to eight months.
What remains unsettled is Iran’s intent. U.S. intelligence agencies have long concluded Iran halted a structured nuclear‑weapons program in 2003, and assessments in recent years have not found evidence that a formal, revived weapons program is under way. The DIA summarized its view in May by saying Iran is “almost certainly not producing nuclear weapons,” while acknowledging Tehran has taken steps in recent years that would make it easier to produce them if it decided to do so.
IAEA Director‑General Rafael Grossi told a French broadcaster on Feb. 18 that the agency had seen no indications Iran was actively developing a nuclear weapon and said there was room on both sides to pursue an agreement. Iran continues to insist its nuclear work is for peaceful purposes.
The IAEA has also noted that Iran is the only non‑nuclear‑weapon state currently producing uranium enriched to this level.
What effect did the previous U.S. strikes have?
U.S. airstrikes in June 2025 struck the Fordow and Natanz enrichment sites and a research complex near Isfahan. The extent of long‑term damage to Iran’s program remains disputed. The president has described the attacks as having “obliterated” the facilities and setting the program back “basically decades.” Grossi told CBS News shortly after the strikes that they inflicted “severe damage” but did not completely eliminate Iran’s capabilities.
The IAEA reported the high‑enriched uranium stockpile remained “in large quantities” after the strikes, though some of it may have become less accessible. Satellite imagery from late January showed roofs and repairs at Natanz and Isfahan, possibly indicating efforts to protect or restore damaged infrastructure. A confidential IAEA document also flagged unexplained activity at sites hit by the U.S.
IAEA inspectors were withdrawn from Iran for safety reasons after the strikes, and Tehran suspended cooperation with the agency in July. The IAEA later reported it had been able to conduct some inspections in the months that followed, but not at the facilities targeted by the strikes.
Iran has downplayed the long‑term impact of the attacks, saying the loss of buildings and machines does not eliminate technical knowledge or the political will to pursue a civilian nuclear program.
How did Iran’s nuclear program develop over time?
Iran’s nuclear work goes back decades, including research before the 1979 Islamic Revolution. By the mid‑1980s, the country had begun developing or acquiring centrifuge technology to enrich uranium. Revelations in 2002 about previously undeclared facilities triggered intensified international scrutiny; the IAEA has said that up until about 2003 Iran pursued a “structured program” that included activities relevant to a nuclear explosive device.
A landmark deal in 2015 — the Joint Comprehensive Plan of Action (JCPOA) — limited Iran’s enrichment levels and stockpiles in exchange for sanctions relief and increased IAEA monitoring. The United States withdrew from that agreement in 2018 and reimposed sanctions under a “maximum pressure” campaign. Subsequent efforts by other parties to revive the JCPOA repeatedly faltered.
Since abandoning the JCPOA limits, Iran has progressively escalated enrichment activities, including producing uranium enriched to roughly 60% for the first time.
Washington has at times pushed Tehran to stop enrichment altogether; Iranian officials have rejected that demand, framing enrichment as a sovereign right tied to peaceful energy and national pride.
Where things stand now
Technically, Iran is closer than it has been in years to having the fissile material needed for a bomb, but there is still uncertainty about whether Tehran has decided to weaponize that capability. U.S. and Iranian officials have maintained intermittent indirect talks even as military forces have been repositioned in the region. The situation remains tense and fluid, with international inspectors and intelligence agencies continuing to monitor Iran’s facilities and stockpiles.