Creates a package of tax changes and incentives aimed at strengthening the U.S. maritime industry. It extends an existing fuel tax exemption to more domestic port-to-port vessel trade, establishes special “maritime prosperity zones,” creates two new investment tax credits for U.S. cargo vessels and for shipyard facility investments, narrows and clarifies rules about qualifying U.S. vessels, excludes certain maritime security and student incentive payments from gross income, and tightens rules on merchant marine capital construction funds (including limits on certain Chinese-made equipment). Most provisions take effect for transactions or tax years beginning after Dec. 31, 2025, with the maritime prosperity zone rule effective on enactment.