In the 64 years since Eisenhower became President, the number of U.S. shipyards capable of building deep-draft, self-propelled, oceangoing naval and/or merchant ships of at least 400 feet in length has declined from 30 to 6 and the number of large ships they built each year has declined from 60 to 7. (The number of big yards is now technically 9 but 3 of those 9 are not active in the market.)
