The DPRK had literally never been to war outside its territory; it’s not a dove but at least it hasn’t invaded multiple sovereign countries like its southern cousin.
China does troop exercises like every single other country in the world.
I mean as long as you consider South Korea part of their territory, sure. There was though the Korean War, where North Korea invaded South Korea. Of course it’s not on the same level as South Korea, but I would imagine that’s more because they literally can’t, they have no resources for it, not because they’re amazingly peaceful people.
The north didn’t invade the south though, no Koreans agreed that the US supported parallel was a permanent division of the country, both North and South fully intended to create a united Korea. Tens of thousands of Koreans were already dead from purges and suppression of uprisings in the south when the operation started. It was literally an ongoing civil war that had momentarily frozen.
I’m not sure on what information you base this claim, but as far as I know the 38th parallel was agreed upon because both the udssr and the US wanted total occupation of Korea for themselves, but they both wanted to potentially avoid an armed conflict so tried a compromise.
Then the north korean part, supported by China and unofficially by the soviet union, invaded the south to establish total control.
