You can bet that Biden backers would have no objections to an American version of this decree.
It’s interesting that in most histories that I’ve read, Maximillian is portrayed as misguided somewhat sympathetic character who bravely went to his death. This Black Decree is never mentioned.
I also find it interesting that while more or less contemporaneous with the American Civil War, how harsh the two sides were in comparison with each other. Only one man was hanged for treason—he cut down an American flag in New Orleans, and only one was hanged for his actions during the war—the governor of the Andersonville P.O.W. camp.