For those who aren't military architecture buffs, the star fort developed in response to artillery that could level the walls of medieval castles. The idea was not to build high, but low, and defend the base of the walls with glacis, berms that could prevent artillery from firing low and bringing down the walls.
Fort McHenry in Baltimore, site of "The Star Spangled Banner", is a pretty cool star fort.
The Statue of Liberty sits in the middle of Fort Wood, built before the War of 1812. There's a number of other star forts that defended NYC.