I think drones are an act of war.
They're just an easy way of disposing of people the US government wants dead, whatever the reason, without giving them a fair trial, and with no regard with the loss of innocent lives, or even the sovereignty of the country where so called «terrorist» has taken shelter.
Also, is much cheaper just to use drones than to go into a full fledged war.
But with drones, you need to ask for permission from local authorities to enter in their airspace;
Nevermind. I guess the USA doesn't even asks for permission.