From that, there is a shortcut to the reasoning that occurs: Intercostal shipping is expensive : Jones Act's fault Can't build ships fast enough : Jones Act's fault Ships are expensive ; Jones Act's fault
The things that the Jones Act mandates are that: Shipping between American ports must be done on American built, owned and crewed.
For example, they will claim that foreign ships can't deliver to Hawaii or Porto Rico and that is why things are expensive there. However: ...although ships can offload cargo and proceed to the contiguous U.S. without picking up any additional cargo intended for delivery to another U.S. location... https://en.wikipedia.org/wiki/Merchant_Marine_Act_of_1920#Ef...
So it is possible for a ship from say China to deliver to Hawaii or Porto Rico, they are just not allowed to pick up cargo to deliver to the US from there.
They will claim with one breath, American labor is too expensive and then turn around and say that we would have a ship building boom if only we didn't mandate that we build ships.
I would agree that American labor is expensive, it is easy to lower costs when you have a LCOL area, don't care about worker protections and don't care about environmental effects.