Let's start here. Let's take a look at the culture the North Korea has right now. There isn't all too much information about the aptly named "Hermit Kingdom", but there have been a few brave souls that have ventured inside and escaped with a glance of what it looks like to be on the inside. The biggest thing is also the scariest; the indoctrination. North Koreans are brainwashed from birth to worship their "great leaders" Kim Il Sung, Kim Jong Il and Kim Jong Un. And when I say worship, I mean literally worship. They hold their leaders in great esteem with a cult-like fanaticism, from how you're supposed to address them, to how you're supposed to take a picture of them. In a style not dissimilar to 1984, everyone feels watched, and no one knows if anyone around them is legitimately loyal to their leader, or just too scared to dissent in any way, shape or form.
The level of education and technology is far behind any of the countries North Korea is threatening to attack. It looks like they're pretty much stuck in the early 80's. There are barely any cars on the road, computers look like this, and warehouses full of modern medical equipment that other countries have donated but none of the North Korean doctors know how to use. A few years ago there was a documentary about a humanitarian doctor that came to North Korea to cure patients suffering from cataracts. Most of them had progressed so badly, that they were completely blind, and when they could finally see, instead of thanking the doctor, all the credit went to their "great leader".
In the same documentary, they interviewed a family and asked them "Can the great leader do anything wrong?" The family just stared back, as if they didn't understand. When they tried to take a picture of Kim Jong Il's statue, the camera man laid down in front of it to get a better angle, and the North Korean "tour guides" went ripshit.
The original idea behind to politics of North Korea was the idea that if they remained completely united and loyal, they could conquer any country, no matter their size, education, training or technology. At least the military branch of North Korean truly believes this, and they're crazy enough to try and follow through with it.
The worst part of this is, Kim Jong Un himself was raised and indoctrinated in this very culture, and he's the one with his finger on the trigger. The threat of a nuclear attack on another country from North Korea is very real. Kim Jong Un seriously believes he can take on the rest of the world and win, and there's only a few ways that a war like that will end. All of them end very quickly.
As soon as North Korea launches a nuclear missile at anyone, war is going to break out. Even if the missile gets taken down by anti-air defenses, it would be an act of extreme, unwarranted aggression, meaning war. If the attack is on the US, the US goes in and slaps their shit. If the attack is on South Korea, the US goes in and slaps their shit. If the attack is on Europe, most of Europe will go in and slap their shit. If North Korea attacks anyone, they get their shit slapped. There is absolutely no favorable outcome for North Korean, not a realistic one at least.
The only real fear is where the North Koreans strike first, because it's the only strike they're going to have. As soon as its out of the way, everyone has an excuse to invade and slap their shit shitless.
So this is my message to North Korea:
Chill the fuck out. You are trying to play a game where the only winning move is not to play.