Since 1871 the Cape Hatteras lighthouse has been a welcome sight for sailors entering the treacherous region off North Carolina's Outer Banks known as the Graveyard of the Atlantic. At 208 feet high, it is the tallest lighthouse in the country and one of the state's most famous landmarks. Through the years, it has withstood the ravages of both humans and nature, weathering numerous violent storms and two wars. But perhaps the gravest threat the structure...