I just showed this to my grandfather (he is German) and he told me to tell you that it was exactly the same reasoning when Nazis started War War 2 in September of 1939.

Many of his friends and family members were saying back then that if you have something against executive branch murdering Polish people, then you should vote Chancellor Hitler out in the next election, because German soldiers are only executing given orders.

And there is exactly no law which requires this. It is entirely a Trump administration directive.