These Iraqi officers must have heard of Nuremberg: their fate would be to hang by the neck until very dead, should they obey this order.
I doubt that any would risk it, if they saw the war was being lost anyway.
Actually the U.S. policy is to reply with nuclear weapons i.e. the oficers in question won't hang they will simply register on gieger counters as they float around the upper reaches of the atmosphere for years to come as radioactive fallout