That headline is a bit dramatic there.. Trump rescinded the order because of the possibility of killing 150 people. Iran’s population is 81+ million.
What are the chances the defense dept had intel that rooshins were on site as advisors on operating fairly sophisticated radar and logistics ? Wouldn’t be the first time, you can bet there were no clandestine ops in Venezuela after Russia inserted their special ops. Russia and China both voiced their support for the ragheads after the tanker minings to keep us at bay by hinting at proxy support. You could see possible hesitation in chancing killing Russians over a drone. Even the Syria missile attack they gave Russians advance warning so there would be no casualties.