The Iran war explained: timeline, key players and what it means for the US

The Iran war began on Feb. 28, 2026, when the United States and Israel launched strikes on Iran. The Pentagon says the strikes killed Supreme Leader Ali Khamenei. A ceasefire in the spring and a U.S.-Iran memorandum in June both broke down. As of mid-October, a U.S. naval blockade of Iran is in place, attacks on shipping around the Strait of Hormuz are at record levels, and mediated talks to end the war are stalled.

For Americans, the war's effects so far have come mainly through oil prices, military deployments and a diplomatic standoff that U.S. officials say turns on Iran's nuclear program. Below is a timeline built from official U.S. and United Nations records and reporting by Reuters, Al Jazeera and CBS News. Casualty counts and battlefield claims vary by source and often cannot be independently verified, so this explainer attributes each claim to whoever made it.

When and how did the Iran war start?

According to the Department of Defense, President Donald Trump approved Operation Epic Fury on Feb. 27, and U.S. strikes began at 1:15 a.m. EST on Feb. 28. Gen. Dan Caine, chairman of the Joint Chiefs, told reporters that more than 100 aircraft flew in the first wave and that U.S. forces hit more than 1,000 targets in the first 24 hours.

Secretary of War Pete Hegseth listed three main goals:

• Destroy Iran's offensive missiles and its capacity to produce them
• Destroy Iran's navy and other security infrastructure
• Ensure Iran never obtains a nuclear weapon

Hegseth said the operation had no fixed timeline and did not include nation-building. The Pentagon's account says the strikes killed Khamenei.

The war followed a smaller round of fighting. In June 2025, U.S. forces struck Iran's Fordow enrichment site in an operation the Pentagon called Midnight Hammer.

What is the timeline of the Iran war?

Some exact dates differ between sources. For example, the UN record does not give a precise date for the April ceasefire, and outlets describe the collapse of the June arrangement in different ways.

Who are the key players in the Iran war?

• United States: President Trump; Secretary of State Marco Rubio; Secretary of War Pete Hegseth; and Gen. Dan Caine, chairman of the Joint Chiefs.
• Iran: The government and the Islamic Revolutionary Guard Corps (IRGC). Rubio has said the IRGC, not Iran's elected leaders, makes the final decisions.
• Israel: It joined the strikes on Feb. 28, and it holds a national election on Oct. 27.
• Gulf states: Bahrain told the UN Security Council it had faced 808 attacks since Feb. 28. Kuwait reported hundreds of drone and missile attacks.
• Mediators: Qatar hosted indirect talks in Doha in late June, according to the UN. CBS News reported in August that Qatar and Pakistan were pressing to restart direct U.S.-Iran talks.
• UN Security Council: Divided. Russia and China vetoed a draft resolution that would have demanded Iran stop attacking ships, and Russia defended Iran's right to self-defense.

Why does the Strait of Hormuz matter?

The strait is the narrow sea lane out of the Persian Gulf, and Gulf oil and gas exporters depend on it. It has been at the center of the war.

• Rising attacks. Reuters, citing maritime security sources, reported at least 12 attacks on oil, gas and other tankers between Sept. 28 and Oct. 5, the highest weekly total of the war. The UN's International Maritime Organization had confirmed nine of those incidents.
• The U.S. blockade. Al Jazeera reported on Oct. 11 that, according to U.S. Central Command, U.S. forces have disabled four commercial vessels, turned back 135 ships and destroyed 10 Iran-linked tankers since the blockade was reimposed in mid-July.
• Reduced oil flows. Al Jazeera, citing data firm Kpler, reported that crude moving through the strait averaged about 8.5 million barrels a day in the week ended Oct. 7, roughly 40% below normal.

Each side blames the other. At a Sept. 23 press conference in New York, Rubio said the only blockade is the U.S. one, imposed because Iran keeps firing on ships. Iran, for its part, wants U.S. support for a deal with Oman on coordinated transit routes through the strait, Al Jazeera reported.

Why did the ceasefire fall apart?

UN records show a ceasefire was agreed in April. Fighting flared again in late June: Iranian drones hit two tankers near Hormuz on June 25, U.S. forces struck Iranian coastal military sites on June 26 and 27, and Iran targeted U.S. sites in Kuwait and Bahrain. Both sides then agreed on June 28 to stop attacking each other, according to a UN Security Council summary.

The two governments also reached a memorandum of understanding in June. Rubio said in September that Iran violated and effectively ended that memorandum when the IRGC attacked shipping. Iran is seeking a return to it, Al Jazeera reported.

What does the Iran war mean for the US?

Gas and oil prices. CBS News reported that Brent crude was about $87 a barrel in late August, up from roughly $72 before the war. Prices at the pump depend on many factors, but sustained disruption in Hormuz tends to push fuel costs higher.

Strain on the military. CBS News reported in August that U.S. officials described stocks of Patriot interceptor missiles in Europe as critically low. It also reported that the aircraft carrier USS Abraham Lincoln had been at sea for more than 250 days.

The nuclear question. Rubio has called preventing an Iranian nuclear weapon the central U.S. goal. He has argued that Iran wants to keep its own uranium enrichment. Vice President JD Vance has said Iran must meaningfully cut its enrichment capacity, Al Jazeera reported, while Iran says it will not give up enrichment entirely.

Politics at home. Rubio said the president has broad authority to impose sanctions and use force regardless of Congress or the midterms. Al Jazeera reported that a breakthrough is not expected before the Nov. 3 U.S. midterm elections.

What happens next?

There is no clear path to a settlement. U.S. officials say they are open to a deal if Iran gives up its nuclear ambitions and its support for proxy groups. Iran says any deal must end fighting on all fronts, including Lebanon, CBS News reported. Meanwhile, the blockade continues and attacks on shipping are rising.

Frequently asked questions

When did the Iran war start?

The war began Feb. 28, 2026, when U.S. and Israeli forces struck Iran, according to the Department of Defense. Trump approved the U.S. operation, named Epic Fury, a day earlier.

Is there a ceasefire between the US and Iran?

Not one that is holding. A ceasefire agreed in April and a memorandum reached in June both broke down, and the U.S. reimposed its naval blockade in mid-July.

What is Operation Epic Fury?

It is the Pentagon's name for the U.S. military campaign against Iran. Officials say its goals are to destroy Iran's missile and naval forces and keep Iran from obtaining a nuclear weapon.

Why is the Strait of Hormuz closed?

Iran has attacked or threatened ships moving through the strait, and the U.S. is blockading Iranian ports. Reuters reported a record week of tanker attacks in early October.

How is the Iran war affecting oil prices?

CBS News reported that Brent crude was about $87 a barrel in late August, compared with roughly $72 before the war. Flows through Hormuz were still about 40% below normal in early October, according to Kpler data cited by Al Jazeera.

Are US-Iran peace talks happening?

Only through mediators. Rubio described mediated contacts in September, and Al Jazeera reported in October that the talks were deadlocked.