South Korea and the United States kicked off their annual joint military drill Monday despite strong protests from North Korea ahead of a summit between the neighboring rivals. The Ulchi Focus Lens drill, which runs through Aug. 31, comes as the two Koreas prepare for the second summit between their leaders since the peninsula was divided after World War II. The first summit was in 2000. The Korean leaders' summit and the military exercise were originally due to overlap, but the summit has been rescheduled to Oct. 2-4 because of extensive flood damage in the North. The joint military exercise - conducted every year since 1975 - is largely a computer-simulated war game, involving about 10,000 US troops in South Korea and abroad, according to the US military.