You mean like rent a private plane and go over there (trying not to be shot down as you land), seek out the big man, perform a citizen's arrest ('illegally' I guess, although I can't say I've read much of North Korean law), get him on the plane, bring him back to your local sheriff's office in rural Mississippi...?
I don't really see that happening, although I would pay very very good money to see Dog the Bounty Hunter (in his prime years) do this.
That's why you wouldn't be good at politics.
Removing someone from ruling position without making necessary coalitions with influencial people inside this country is like resetting diplomatic relations. You can get someone better, you can get someone even worse as new ruler. And this is too risky.
Making coalition with influencial people is also hard, because they are afraid that losing power will inevitably push them to jail or death sentence and it's hard to convince that you will keep your word.
What if abducting Kim Jong Un will result in army ruling country and deciding to attack South Korea in revenge?