"Word that a South Korean naval ship sank in the tense waters around the disputed maritime border with communist North Korea set off panic:"
Sure set off a panic on these forums: See Topic: BREAKING: South Korean warship sinking after torpedo attack from North Korean Ship.
"It's looking more and more like it was just an accident that happens on a ship," Carl Baker, an expert on Korean military relations at the Pacific Forum CSIS think tank in Honolulu, said by telephone."
I don't really think the US and South Korean Militaries panic. This type of stuff has been going on for 60 years.