If Turtle had sunk Admiral Howe's flagship

What follows if Turtle succeeds in its 1776 attack on Admiral Howe's flagship in New York Harbor?

Navies would pursue underwater harbor defenses and begin thinking earlier about false bottoms, double bottoms, or protective structures around a ship's keel.

A successful Turtle attack would demonstrate that an anchored warship could be struck from below. Harbor defences against underwater attackers would become an immediate priority. Designers might also experiment with a false bottom, double bottom, or protective structure around the keel to keep an explosive from reaching the main hull directly.