Harrison Jacobs/Business Insider
The Oak Hill is a Harper's Ferry-class vessel, a type of amphibious warfare-focused ship that would be near the frontlines of any sea-based invasion. While the ship is equipped with a variety of missiles, guns, and other counter-measures, the real power is what the ship houses on the inside. The Oak Hill has a well-dock, where it can load and unload boats, amphibious vehicles, troops, and landing craft.
If a D-Day-type landing happened in this day and age, the Oak Hill would be one of the ships launching troop transports and vehicles onto the beachhead.
Business Insider recently got a tour of the ship, while it's in dock at midtown Manhattan's Pier 92, to see what makes the ship battle-ready for an amphibious invasion.