They have a WWI economy. The GDP of the entire country (26 million) is the same size as the GDP of Lexington, Kentucky (roughly $12 billion.)
The North Koreans have a WWII military.
How hard would they be to beat?
It appears that they have no inhibitions against using poison gas. They used a nerve agent to kill the leader's half-brother.
The leader is ruthless and cultivates the image of addressing perceived slights with over-kill. You know, like killing a minion who fell asleep in a meeting with a mortar round.
|At first look, North Korea only has a few weapon types that can reach Seoul. They would have to advance about 20 km (12 miles) to be able to saturate Seoul.|
|It gets more ominous when you look at prevailing wind direction. The rounds don't have to reach Seoul. The wind will blow it the rest of the way. Data from Gimpo Airport|
The topography is not well suited to armor. Even if armor was activated, it would be a bear to keep fueled and armed in a toxic environment.