> Something like this would never be put into writing today

Because we don’t need rules like that today. America was a very different place than it is now. Those rules were there, not because they were shoot happy maniacs, or because they didn’t care about being “PC”, but because it was much more dangerous back then. It is the same reason that US soldiers stationed in Germany don’t have the same rules of engagement as soldiers in Afghanistan.

American civilians who had made a decided effort to commit a federal felony. Also "ordering soliders to kill American civilians" attempts to color the situation in an unfavorable light, as if the soldiers had alternatives, or the situation didn't fully warrant it.

There's no reason that killing armed gangsters wasn't totally justified in this case.