Jones Act is not what killed the US Merchant Marine Fleet. Globalization is what killed it.
The Jones Act made sense when it was implemented in the 1920s while America was the world's leading ship builder, the shipping industry was heavily subsidized, and there was no alternative to shipping things by water. But after the subsidies stopped, and shipbuilding in america started to lose its competitiveness, and we built a massive interstate highway system that made transport by truck economical, the Jones Act proved far too restrictive. The more expensive domestic water shipping got, the less demand there was for ships, the less demand there was for ships, the more it cost to build ships domestically, the more it cost to build ships domestically, the more expensive domestic water shipping got.
There are alternative and better ways to keep the us merchant fleet alive, and even make it thrive, than keeping the current status quo which is obviously not working.
"Protectionism isn't what killed the US industry. Having any overseas competition whatsoever is what killed the US industry." This is farcical.
If globalisation is when the market lacks protectionism and as a result the manufacturing all moves to cheaper shores, then this was not globalisation by dint of US shipbuilding having abundant protectionism.
It can, however, make us much better off, by for example allowing US companies to buy foreign ships to do tasks that currently are covered by Jones Act, and as a result are not done at all.
For example, we’d be able to ship gas from American oil fields in the South to consumers in the North, where there missing or insufficient pipeline capacity. Right now, Jones Act forces US consumers in the North to buy foreign gas.
Couple years back, before the Russia-Ukraine war, Russian Gazprom was making nice profit on the following run: 1) sail to Northeastern US, sell it Russian LNG 2) sail to Gulf of Mexico to buy American LNG for cheaper than it sold Russian gas to Americans in the North 3) sail elsewhere in the world to sell them American gas, eg to Europe or Africa.
This was only possible because Jones Act makes it impossible to ship LNG from Southern US to North. There are literally no vessels that can do it. It already cripples our ability to move things around.