Defense Secretary Pete Hegseth said early Monday the U.S. military operation in Iran is  “laser-focused” as the U.S. and Israeli military operation against Iran continued into a third day.  

“Destroy Iranian missiles, destroy Iranian missile production, destroy their navy and other security infrastructure and they will never have nuclear weapons,” said Hesgeth, who was joined by the Chairman of the Joint Chiefs of Staff Gen. Dan Caine. 

Hegseth declined to give a timeframe for the operation, but he insisted it would not be “endless.” 

“This is not Iraq,” Hegseth said. “This is not endless. I was there for both — our generation knows better, and so does this president. He called the last 20 years of nation-building wars dumb and he’s right. This is the opposite. This operation is a clear, devastating, decisive mission: Destroy the missile threat, destroy the navy, no nukes.” 

Hegseth said there are no U.S. military “boots on the ground” in Iran right now, but said he would not “go into the exercise of what we will or will not do” in the future. 

The Pentagon said Monday that a fourth American service member had been killed in the mission, following the announcement of the deaths of three U.S. service members in Kuwait over the weekend. Hegseth said that the four service members had been killed after a tactical commander center had been hit. 

On Monday, Kuwait shot down three U.S. F-15s in what CENTCOM called a “friendly fire incident,” but all crewmembers were safe. Smoke rose, meanwhile, from the U.S. Embassy in Kuwait after an apparent Iranian missile strike.

Caine said it will “take some time for us to conduct a battle damage assessment, and the targeting that CENTCOM will run will take those things into effect.” 

At least 11 people have been killed in Israel. The Iranian Red Crescent says 555 people have been killed in Iran.

President Trump said Sunday that the joint military operation would continue “until all of our objectives are achieved,” and that could be “four weeks or less,” but that more American casualties are possible.

The U.S. and Israel launched a massive military operation against Iran over the weekend, which included striking Iran’s Supreme Leader Ayatollah Ali Khamenei’s compound in Tehran and killing him. 

Caine said Monday that Mr. Trump gave the order Friday afternoon that “Operation Epic Fury is approved. No aborts. Good luck.” 

After that call was made, Caine said air defense batteries readied themselves, pilots and crews rehearsed strike packages for the final time, and air crews began loading their final weapons, while two–character strike groups began moving toward their final launch points across the globe. These movements occurred as the Defense Department’s operation centers “came alive” at the Pentagon and in Tampa, Florida. 

At 9:45 a.m. local time, or 1:15 a.m. ET, Caine said more than 100 aircraft were launched from land and sea as “electronic attack bombers from the state and unmanned platforms forming a single synchronized wave.” 

“This was a daylight strike based on their trigger event conducted by the threat, the defense forces, enabled by the U.S intelligence community,” Caine said. 

Caine said the first shooters at sea were Tomahawks unleashed by the U.S. Navy, which “closed in on Iranian naval forces to conduct strikes across the southern flank in Iran on the ground.”  

Hegseth on Monday accused Iran of having started the war, saying Iran’s “stubborn and self-evident nuclear pursuit” as well as “targeting global shipping lines.” 

“Iran had a conventional gun to our head as they tried to lie their way to a nuclear bomb,” Hegseth said.