The UN, which sponsored the international military force that pushed back the invading North Korean troops in South Korea during 1950 is still technically in charge. This in early July 2016 the UN made a rare move and authorized South Korean and American troops to carry weapons (besides pistols) into the DMZ (the 257 kilometer long demilitarized zone that marks where the front line was in 1953). The DMZ is four kilometers wide and no weapons or troops are supposed to enter except by prior agreement by both sides. North Korea has been violating this for decades and also sending in patrols with heavy weapons. Now the UN authorizes the South Korean and American troops to officially send troops into the DMZ, as needed, armed with machine-guns (up to 12.7mm), 40mm automatic grenade launchers, 57mm recoilless rifles, 60mm and 81mm mortars, Claymore anti-personnel mines and hand grenades. The UN has given up on trying to negotiate with North Korea and this rare edict is another sign of this frustration.
The UN long ago delegated to the United States the actual responsibility for protecting South Korea but since 2003 North Korea has been gradually withdrawing from the terms of the 1953 ceasefire agreement that ended the fighting, but not the war. All attempts at negotiating an end of the war since then have failed. The three years (1950-53) of fighting caused 325,000 American casualties (including 33,651 dead). South Korean troops suffered 360,000 casualties, while other nations fighting North Korea suffered 15,000 casualties. The communist forces suffered 1.5 million casualties. There were several million civilian casualties.