Repeal the Jones Act which requires that all shipping within the US is done on US ships and sailors. Also outsource military shipbuilding to allies.
This law has not stimulated domestic shipping or shipbuilding but has instead caused it to stagnate and decline. This is not well known but US shipbuilding is an expensive and slow disaster. The Littoral Combat Ship program was an enormous waste of time and money, and our deficit is exploding.
Korea and Japan are far more efficient at building ships. We could get 100% more out of our ship budget by outsourcing shipbuilding. They would have to agree to outsource some other contracting to us in exchange, submarines like in the AUKUS agreement or AI services.