For South Korean national security officials, the memory of the 1987 bombing of a Korean Air Flight 10 months before the 1988 Summer Olympics in Seoul is still fresh. And with the PyeongChang Winter Olympics beginning Friday, officials are scrambling to prepare for nearly every conceivable terror scenario, from a terrorist taking hostages, to unleashing a chemical attack at one of the Olympic venues to a drone dropping an explosive from the sky.
The South Korean government isn't taking any chances: It has banned 36,000 people from entering the country due to security issues. The government has assembled a security force of 60,000 - including 50,000 soldiers. A law enforcement center has been set up in Seoul to monitor potential threats. South Korean marines have been training with their American counterparts to test their competence in the snow and cold, as CBS reports.
"We've covered reconnaissance skills as well as critical combat skills in a cold-weather mountainous environment," U.S. Marine Captain Thomas Rigby told CBS News correspondent Ben Tracy.
Despite the detente in North-South relations - and the decision to form a joint North-South women's ice hockey team, which played its first friendly match against Sweden yesterday.
While the US and South Korea have agreed to suspend military exercises until after the Games, the history of hostilities, combined with North Korea's accelerating progress toward building a reliable nuclear weapon, has made security services wary.
One concern is how law enforcement would respond to a devastating cyber attack. The North is well known for its cyber warfare skills. South Korea has hired an independent cybersecurity firm to guard against attacks.
After all, the North is only 50 miles from PyeongChang.