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US Defence Secretary Pete Hegseth said on Monday that the country would not get bogged down in an open-ended war against Iran as it had after the 2003 invasion of Iraq.
He also said additional US forces were to arrive in the region and declined to rule out future ground missions in Iran.
“To the media outlets and political left screaming ‘endless wars’, stop. This is not Iraq. This is not endless,” he told a Pentagon media conference. “No stupid rules of engagement, no nation building or no democracy-building exercise, no politically correct wars. We fight to win and we don’t waste time.”
Mr Hegseth, who previously served in Iraq and Afghanistan, said America's ambitions for Iran “are not utopian – they are realistic”.
“Our generation knows better and so does this President. This operation is a clear, devastating, decisive mission,” he added.
In his first public remarks since the war against Iran began on Saturday, Mr Hegseth said Tehran had been trying to build a “shield” to protect its nuclear weapons programme. “Iran was building powerful missiles and drones to create a conventional shield for their nuclear blackmail ambitions,” he said.
Speaking alongside Mr Hegseth, Gen Dan Caine, Chairman of the Joint Chiefs of Staff, said additional US troops would arrive in the region on Monday. Central Command chief Admiral Brad Cooper will "receive additional forces even today", Gen Caine said.
"This rapid build up of forces demonstrated the Joint Forces’ ability to adapt and project power at the time and place of our nation’s choosing."
When asked how many troops are in the region, he said: “I don’t want to talk specifics, because that would tip the enemy off. I think we’re just about where we want to be in terms of total combat capacity and total combat power for Admiral Cooper."
He added that the current deployment included “thousands of service members from all branches, hundreds of advanced fourth and fifth-generation fighters, dozens of refuelling tankers, the [USS Abraham] Lincoln and Carrier Strike Group and their embarked air wings".
Mr Hegseth said there were no American troops on the ground in Iran, but he did not rule out sending forces into the country. He said he was "not going to go into the exercise of what we will or will not do".
“We’ll go as far as we need to go to defend American interests," he added. "We’re not dumb about it. You don’t have to roll 200,000 people there and stay for 20 years."
