North Korea’s announcement this week that it is preparing plans to fire four missiles near the U.S. Pacific territory of Guam has heightened the tensions between Kim Jong Un and President Donald Trump. After Trump on Tuesday appeared to threaten nuclear war against North Korea by promising “fire and fury like the world has never seen,” Pyongyang responded Wednesday that it was “carefully examining the operational plan for making an enveloping fire at the areas around Guam,” according to Reuters. As many Americans wade through the back-and-forth threats between the two nations, they may be wondering how exactly Guam ended up in the middle of this war of words.