Another blow to treasure hunters came in 2001, when UNESCO established the Convention on the Protection of the Underwater Cultural Heritage, which protects all underwater traces of human existence that are more than 100 years old. Though the United States has not ratified this convention, 58 countries have signed on, including Spain, France, and Italy, and the ripple effect is felt by all.
Once the Sunken Military Craft Act came into effect in 2004, countries had two layers of U.S. legal protection. The military craft act has had huge repercussions for treasure hunters since most European ships sent sailing on the high seas centuries ago carried artillery and were effectively warships, even when they had no intention of going to war .