Huh? The Jones Act was supposed to
help American shipbuilding. It's a requirement that vessels which operate between US ports must be made in the US, crewed by the US, and flagged to the US. It didn't help much, but that was the plan.
China's shipbuilding industry is so big that their aircraft carriers are being constructed by shipyards that make large cargo ships. Aerial photos show shipyards with drydocks full of cargo ships, with an warship or two mixed in.
US warships are mostly built by Newport News Shipbuilding and Dry Dock, and the Bath Iron Works, which don't make civilian ships. There's little economy of scale in US warship construction. Some years ago, the head of Newport News told Congress that if they'd order two carriers at the same time, the company would throw in a third one for free. Congress declined the offer.
The PLAN now has more warships than the US Navy. Fewer carriers, but that's being fixed. China's carriers are getting better. The type 001 carrier was a refurbished Russian carrier. The type 002 was a smaller ski-jump carrier. The type 003 was comparable to the US Kitty Hawk class. Whether the next carrier will be nuclear powered hasn't been announced.