North Korea has been sending worrisome signals to the world.
It recently announced the withdrawal of all North Korean workers from an industrial zone jointly operated with South Korea. That's after repeated threatening messages from Pyongyang toward the South and the United States.
In fact, there's speculation that the North could be planning to launch a missile against an American target this week.
The experts don't seem to think that's likely.
But the question remains: which American target could be within reach of a North Korean missile?
The range of that missile is estimated at about 2,500 miles. That means the West Coast is safely out of range.
But not an American island territory in the Pacific.
This territory is about 2,100 miles from North Korea, as the missile flies.
Magellan gets credit for discovering this island in 1521.
Today this western-most US territory is home to a major American military base.
The island in the Pacific where the US military has a big presence and which could potentially be reached by a North Korean missile.
The answer is Guam.
Mark Ombrello teaches Korean history at the University of Guam. He says his students have heard that their island may be targeted by North Korea. But they're not panicking.
"I suppose it's sort of like preparing for a typhoon," Ombrello says. "We get typhoons and we know how to respond to typhoons, but this is much more existential than a typhoon."
More existential than a typhoon. But not as frightening?
"It's obviously very disturbing, and it's very scary if you think about it, the possibility of a missile being launched at us, and coming close to us, or even exploding on us," he says. "That's something that I don't know how to get my own head around. But at the same time, while, in my case, having done work on Korean history, it's really hard to say all of this isn't just talk."
But talk can have a chilling effect on a big source of income for Guam: tourism. But so far, says Ombrello, talk of a missile strike hasn't scared visitors away.
"This whole threat from North Korea hasn't affected the visitor industry in any way," he says. "In fact we had a marathon over the weekend, an international marathon, and there didn't seem to be any real scare over what's going on."
As for rumors that a missile targeting Guam could be launched this week, people on Guam seem pretty laid back about it.
Though some wonder whether they're supposed to be more worried than they are.
"I had a discussion with one of my colleagues, she was hoping that more would be revealed, in terms of what we should be doing to get prepared," he says. "I mean, is it time that we act like a typhoon is coming and get canned goods and do all these other things that we normally do when we think a natural disaster is imminent? I guess we'll just have to see how things sort of unfold."