PlutoniumPlutonium is a radioactive chemical element with the symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, and forms a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation states. It reacts with carbon, halogens, nitrogen, silicon, and hydrogen. When exposed to moist air, it forms oxides and hydrides that can expand the sample up to 70% in volume, which in turn flake off as a powder that is pyrophoric.
Korean Armistice AgreementThe Korean Armistice Agreement (한국정전협정 / 조선정전협정; ) is an armistice that brought about a complete cessation of hostilities of the Korean War. It was signed by United States Army Lieutenant General William Harrison Jr. and General Mark W. Clark representing the United Nations Command (UNC), North Korea leader Kim Il Sung and General Nam Il representing the Korean People's Army (KPA), and Peng Dehuai representing the Chinese People's Volunteer Army (PVA).
North Korea and weapons of mass destructionNorth Korea has a military nuclear weapons program and, as of early 2020, is estimated to have an arsenal of approximately 30 to 40 nuclear weapons and sufficient production of fissile material for six to seven nuclear weapons per year. North Korea has also stockpiled a significant quantity of chemical and biological weapons. In 2003, North Korea withdrew from the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). Since 2006, the country has been conducting a series of six nuclear tests at increasing levels of expertise, prompting the imposition of sanctions.
Treaty on the Non-Proliferation of Nuclear WeaponsThe Treaty on the Non-Proliferation of Nuclear Weapons, commonly known as the Non-Proliferation Treaty or NPT, is an international treaty whose objective is to prevent the spread of nuclear weapons and weapons technology, to promote cooperation in the peaceful uses of nuclear energy, and to further the goal of achieving nuclear disarmament and general and complete disarmament. Between 1965 and 1968, the treaty was negotiated by the Eighteen Nation Committee on Disarmament, a United Nations-sponsored organization based in Geneva, Switzerland.
Korean Demilitarized ZoneThe Korean Demilitarized Zone () is a strip of land running across the Korean Peninsula near the 38th parallel north. The demilitarized zone (DMZ) is a border barrier that divides the peninsula roughly in half. It was established to serve as a buffer zone between the countries of North Korea and South Korea under the provisions of the Korean Armistice Agreement in 1953, an agreement between North Korea, China, and the United Nations Command. The DMZ is long and about wide.