Since the end of the Korean war, when Washington fought alongside Seoul against the North, the US has had troops stationed in South Korea.
About 29,000 US soldiers are based in the South, under a security agreement reached after the war ended in 1953.
Each year, the two countries conduct military drills, often called war games.
Washington has described the drills as defensive in nature, but Pyongyang says they are a rehearsal for invasion and has long called for them to end.
‘Gasoline on fire’
There are usually two sets of exercises every year, in spring and autumn, involving a massive number of troops and military hardware.
Both involve land, sea and air military drills and computer simulations. In recent years, they have also involved practice drills for terror and chemical attacks.
North Korea has condemned the drills as an unacceptable act of aggression, provocation and threat.
Over the years, state media…