A Wisconsin historian is shedding light on the current crisis in North Korea.
North Korea and the United States have a long history, and tension between the two is nothing new.
Jeff Leigh, a history professor at UW-Marathon County, has been watching the situation unfold. Leigh says the tension dates back to the Korean War, which started in 1950.
The country was divided and the United States fought along side South Korean troops.
"The United States (would) then provide 88 percent of the troops in what becomes known as the Korean war, as what they perceived as unprovoked North Korean aggression," said Leigh.
Both sides agreed to a cease fire three years after the war started, but a peace treaty was never signed.
"The war is not technically over. But on both sides, there seems to be little inclination to restarting it," said Leigh.
Leigh says this latest threat is just one of many.
"There are a lot of provocations, there's a lot of chest pumping, a lot of language, but there seems to be little desire to start a full on military engagement from either side," said Leigh.
But threats have also come with attempts to repair the relationship. At this point, those attempts have been unsuccessful.
"They have certainly maintained their military ties with South Korea. They have not allowed North Korea to bluster and bully them, but at the same time, they've maintained the door open for further negotiations," said Leigh.
History experts say North Korea has problems of its own.
"North Korea really is an unusual country, very much alone in the world, very much cut off, even at the governmental level, from most of everything else happening. So, there is a different sort of mentality there and a great deal of fear of the entire rest of the world," Leigh told Newsline 9.
The rest of the world is looking on, watching for North Korea's next move.