Unless you've spent the last year in a fallout shelter with no wi-fi, you know that North Korea and the United States are on the verge of nuclear war (so you might as well head back to the bunker). But few people know why North Korea hates the US. According to John Oliver, the rogue nation's animosity stems from leader Kim Jong-un's fears of self-preservation and the North Korean people's anti-American indoctrination. 

"Kim Jong-un is terrified of losing power," the 'Last Week Tonight' host said on yesterday's episode. "And while we love to present him as a madman, many experts believe that his actions are motivated by rational self-preservation. He has seen leaders like Saddam Hussein and Muammar Gaddafi scale back their nuclear programs only to be overthrown either by the US or by their own people and die gruesome deaths. And it's true that dictators generally don't end their careers like disgraced American politicians - with a stint on 'Dancing with the Stars.'"

That's why Kim Jong-un has continued his family's dynastic agenda to build up the North Korean army - the fourth largest military in the world. Which is impressive as well as depressing considering that the country is so poor, it's economy is roughly the size of Birmingham, Alabama - one small city in America's 4th poorest state.

So you might think blowing what little money the country has on the military would make Kim Jong-un unpopular with his impoverished and oppressed people. But he and his predecessors have managed to keep dissent at bay by convincing North Koreans that the military is the only thing protecting their country from being ransacked by bloodthirsty outsiders.

"And that is where we come in," Oliver explained. "Because the most dominant and useful villain in North Korea's narrative is the United States. And it is not like that came out of nowhere. We sided with the South during the Korean War. And while many Americans may have forgotten just how devastating that war was, the North Koreans certainly haven't. They have an entire museum dedicated to American war atrocities."

Some of those alleged events include accusations of vampirism and cannibalism. Seriously. Museum visitors are taught that American soldiers once captured a young woman, stabbed her repeatedly with a spear, drank her blood, cut off the flesh of her thighs and ate it raw.

But Kim Jong-un's people are indoctrinated with hate for the United States long before entering that museum. Anti-Americanism is rife in the North Korean school curriculum, where children are taught simple lessons like subtraction by being asked, "If there are 4 American bastards, and you kill two, how many American bastards are left to kill?" That's an actual lesson related by a North Korean defector.

So it's not surprising that North Koreans approve of Kim Jong-un's military program. "The notion that North Korea is working on a bomb that can kill all the American bastards is a tremendous source of national pride," Oliver said. "There have been stamps depicting missiles hurtling toward the US capital. And a few years ago, they produced a video depicting the destruction of New York set to the least appropriate song imaginable [the humanitarian anthem 'We Are the World.']"

Now John Oliver is extending a musical olive branch by recruiting 'Weird Al' Yankovic to perform a song for the North Korean people on their favorite instrument - the accordion. Yes, North Koreans love the accordion so much, they call it 'the people's instrument' (which sounds like a special thermometer for checking the temperature of whatever The Rock's been cooking all these years).

Check out Oliver's full commentary and Weird Al's song in the clip below. And scroll down a bit further for a rocking North Korean cover of A-ha's 'Take on Me' played on the accordion.