All Korean men must join the military for two years. If something scary happens, it's the boys from my English 101 class who would go to war. As a university professor in Korea, I'd ask my students about North Korea's military actions. They'd say:
"Whatever, it's nothing new. They've done this every year for the past 50 years!"
"We have America on our side."
"North Korea is like an ugly, fat man at the beach flexing his muscles trying to impress people. But nobody cares."
Most South Koreans usually don't give two thoughts to the nation that abuts them. Kim Jong Un and his country are like a next-door neighbor that sometimes makes a big stink because somebody plays loud music.
Some students want a united Korea; some don't. A united nation would be, well, united. Hooray!
However, a united Korea would also mean spreading South Korean wealth. Folks in Seoul have been working 60-hour weeks for decades. They don't feel like tossing that cash to North Koreans who think their last three supreme leaders have never pooped before (Google it).
South Koreans also fear taxes would rise: Many roads, schools and powers plants need to be built. The already-crowded Seoul (10 million people) would become even more crowded.
My students worry about North Korea taking the lead on the unification process. Would their "funny" rules be enacted and enforced? Would they need to learn how to speak each other's languages? Korean dialects in the North and South are not the same.
Then President Trump came along. My students wonder if his speeches are translated poorly or he's just a terrible speaker. A few friends think he's ugly. I haven't really heard anything too positive about him. Maybe I haven't listened hard enough.
The U.S. president angered some South Koreans (and just about everybody else not wearing a MAGA hat) because he cancelled war games outside of Seoul and then planned a military parade in Washington. South Koreans feel like they are being stood up by an old friend. "The U.S. almost always cooks a nice dinner for us, but now they say they want to save money. But then they cook at their own house for nobody but themselves!"
South Koreans helped the U.S. in the Korean War, World War II and Vietnam. Isn't that how allies work?
On top of that, North Korea has two pretty significant allies. South Korea can butt heads with its northern nemesis, but not Russia or China. However, these "allies" seem to think North Korea is their drunken idiot acquaintance picking fights at the bar.
My Korean students love violence, but only in the movies. I've never heard them brag about a fistfight. They want things to remain the way they were, if that's possible. I have no idea about solutions, but I know that most Koreans don't want a war or an enemy. But they'd like help and confidence from their friends.