Dreadnought was the first modern battleship completed, but not the first designed. That honor went to a pair of American battleships, South Carolina and Michigan. Larger only than the Espana class dreadnoughts, Michigan minimally, if efficiently, fulfilled the requirements of a dreadnought battleship. Congress limited the size of Michigan to more or less the same as that of the Connecticut class pre-dreadnought battleships, about 16000 tons, or 2500 tons smaller than Dreadnought. Onto that small frame the architects managed to pack 8 12″ guns in four twin turrets. The most advanced element of the design was turret distribution. While most other navies played with wing turrents (gun turrets set off the center line, and thus incapable of firing a broadside in either direction), Michigan was built with superfiring turrets, where the second turret on each side of the ship was elevated above the first. This allowed all of the guns to fire in a broadside in either direction. This arrangement was maintained in the rest of the US battleship fleet, and eventually spread to the rest of the world’s navies.
Unfortunately, because of her small size Michigan lacked the machinery to make more than 18 knots. Dreadnought, on the other hand, could make 21 knots. The next class of American battleships (and all that followed them) could also make 21 knots, which had the effect of rendering South Carolina and Michigan obsolete shortly after their completion. Unable to keep up with the main US battle squadron, Michigan would best have been employed as reinforcement for a squadron of pre-dreadnoughts. In any case, Michigan never saw combat outside of the action off Vera Cruz in 1914, when Woodrow Wilson unleashed most of the firepower of the US Navy against a small Mexican city. Michigan was taken out of service shortly after World War I, and was scrapped as per the 1922 Washington Naval Treaty.
Michigan and South Carolina were also notable for being the first US battleships 
constructed with cage masts. Earlier US ships had been built with more conventional masts, although by 1910 most had been refitted with cage masts. Cage masts distinguished American ships from those of any other navy in the world. They were extremely fire resistant (shells simply passed through them), but tended to restrict angles of fire for anti-aircraft guns, although this was not an important consideration in 1908. Every battleship up until West Virginia (completed in 1922) carried cage masts. The experience of Michigan also, indirectly, helped lead to the end of the cage mast era. In 1918, gale force winds bent the forward mast of Michigan all the way down to the deck. US battleships modernized during the interwar period lost their cage masts, although four of the ships at Pearl Harbor (California, Tennessee, Maryland, and West Virginia) still had theirs on the day of the attack. Two ships (Maryland and Colorado) would retain their cage masts all the way until their disposal dates in 1959.
