The USS New York, built with steel salvaged from the fallen Twin Towers, entered New York Harbor under the Verranzano-Narrows Bridge Monday and paused for a moment in the waters off Ground Zero to honor those lost in the terrorist attacks of Sept. 11, 2001. A detail aboard the 684-foot, $1.2-billion amphibious assault vessel fired a 21-gun salute from the fantail of the ship.USS New York (LPD-21), the fifth San Antonio-class amphibious transport dock of the fleet.