North Korea is all bark and no bite. North Korea benefits China by acting as a buffer and benefits the US by strengthening ties between the US and South Korea and Japan. There is no interest in changing this arrangement.
Russia didn’t get this way over night. The USSR collapsed and the US capitalized on the situation by enforcing markets in a way to grab wealth. There were many opportunities to rehabilitate and allow Russia to participate in the world as a peer but that went against the US need for an enemy and to dominate them, as evidenced by the Wolfowitz doctrine. Russia’s economy was terrible and Putin did well for himself betting on oil which gave the Russian economy some stability and which is how he got popular. You’ll find that the price of oil collapsed in 2014 and the protests were happening in Ukraine around that time threatening the puppet he had there.