Certainly that is how Jamie Bellush, the victim's husband, sees it. But Miller has an uphill battle. Most nations of the world, like Mexico, do not use capital punishment. Most of them will not agree to help the United States carry it out. Instead, Mexico chose the lengthy extradition process.
Extradition is a fairly recent invention in human history.
Nations did not begin signing formal treaties until the 1700s. Before then, if you wanted to pluck somebody out of another country, you did it either by force, by trick, or by the consent of the other side's ruler. They require that the accused's acts be recognized as a crime in both places. They require that the accused be tried only for the specific crime alleged. They generally refuse to extradite for purely political crimes.