Trading crimes was a plot device in the movie "Strangers on a Train". Why can't government "leaders" do the same?

A nifty game where the person who is murdered has no tie to the killer or the person who orders the hit.

So Putin and the Saudi Crown Prince can take turns taking out the enemies of the john of don per his list and he will ever so gladly engage in reciprocity and order the hits of their enemies.  I expect they will have to pay a royalty to the storyline idea orginator but so what? They are all OBSCENELY RICH so money's no object. Of course their governments will pay for it in a line item cleverly disguised as something else. Any suggestions?  What would YOU name such an account to not cause any suspicion?