The battle over control of the world’s oceans has increased over the past few decades due to the discovery of vast mineral and fuel resources located under the sea. In 1958, the United Nations held the first Conference on the Law of the Sea. This conference established territorial seas, measuring 12 nautical miles (22.24 kilometers) from the shore of coastal nations that are under the full control of that country. (The United States, along with such countries as North Korea, Chad, Liberia, and Iran, have refused to sign the treaty.) Additionally, countries have mineral, fuel, and fishing rights in an Exclusive Economic Zone (EEZ) that spans 200 nautical miles (370.6 kilometers) from shore. Problems arise when two countries’ zones overlap. Median lines between countries have been drawn in most cases, but there are still many areas of disagreement.