Putin's dialogue with Trump has been diplomatic/positive until late. He has also been excessively diplomatic with the West outside of occasional threats that he inserts into public statements- as if he isn't at war with them publicly.
North Korea is an ally with Russia (they give Putin rockstar treatment whenever he visits- same as with China). China has a mutual defense pact with North Korea too. Afghanistan is so poor that they have little to offer except fighters.
North Korea has very large ammunition production capability along with stockpiles which is its trump card.