From the article:

After nearly a decade of loudly complaining about the fact that modern US aircraft carriers use electromagnetic systems to launch fighter jets instead of steam-powered catapults, Donald Trump has directed the Pentagon to redesign a new aircraft carrier to replace the modern system with the old-fashioned catapults he prefers.

Trump signed a national security memorandum on Thursday directing the defense secretary, Pete Hegseth, and the acting navy secretary, Hung Cao, to make the change he has had his heart set on since at least 2017, when he first described his idea to Time magazine.

The memorandum gives the Pentagon leaders 60 days to come up with “a plan on the required measures to replace the Electromagnetic Aircraft Launch System and Advanced Weapons Elevators with steam and hydraulic systems for the construction of” the USS Doris Miller, a Ford-class aircraft carrier, which is already two years behind schedule.

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According to the Wall Street Journal, which first reported the order, senior US navy and industry leaders “have resisted the move due to the enormous expense of tearing out such a complex system that was integral to the design” of the latest aircraft carriers.

General Atomics, the company that builds the electromagnetic aircraft launch system for the Ford-class carriers, said Trump’s decision to revert to steam “warrants careful reconsideration”. The company told the Journal its work on the new ship is nearly 50% complete and “changing course now would introduce significant cost, schedule, and integration risks”.