If the United States built an iron 84-gun ship in 1850

What if the US Navy built two steam-powered, iron, 84-gun warships in 1850?

Britain could answer with roughly eight ships or much larger first-rates, accelerating the naval competition.

The scenario gives the United States two iron, two-deck ships with eighty-four 11-inch Dahlgren guns in 1850. Steam propulsion is assumed in the comparison with Warrior. Britain could respond by building roughly eight ships or developing three-deck first-rates with about 160 guns instead of 120. These are suggested responses to a sudden American lead, without a settled British design.