Answer :
American shipbuilding started out as a necessity, grew as maritime traffic increased, fell when industrialization attracted its investors, and then resurrected itself during World War II.
The glorious years had started to wane by the late 1850s. More tons were launched from shipyards in Maine and Massachusetts than from any other state, but these yards did not manufacture steamships, whereas beyond New England, shipyards realized that steam, not sail, was the future. While both sides made notable advancements in naval construction during the Civil War, commercial shipbuilding suffered greatly. Some American merchants sold their ships to foreign owners as a result of Confederate raids on Union ships. American tonnage in international trade was down to a third by the end of the decade in 1840 from half in the late 1850s.
learn more about shipbuilding here:
https://brainly.com/question/12594305
#SPJ4
