Security is a top concern at every Olympics, where athletes and fans in scattered venues can be difficult to protect. But rarely do they take place in the shadow of a nuclear standoff, as is the case with the Winter Games that open next week here in South Korea.

Nearly 3,000 athletes from 92 nations and 100,000 spectators per day are expected to converge on the area around Pyeongchang, 50 miles from the North Korean border, for what organizers say will be the largest-ever Winter Games. The South has mobilized tens of thousands of security personnel — including 50,000 soldiers — in what may be the most militarized security force in Olympic history. Continue reading.