Nation-state actors do this kind of stuff all the time, and they're difficult to defend against because they tend to be well-funded and therefore able to hire t

Nation-state actors do this kind of stuff all the time, and they're difficult to defend against because they tend to be well-funded and therefore able to hire talent, have resources, and spend money on intelligence and 0days. And they're immune from prosecution unless they're stupid enough to travel to a hostile state. North Korea really does spend a lot of money on this, and so does Russia and China. And US and Israel, for that matter.