Aircraft in international airspace. Subs in the open seas and ships beyond territorial limits. Satellites in space. And then invite them to do the same to us. Reciprocally Understood Military Potential.
Surveillance also means all manner of electronic eavesdropping.
Unfortunately, granting our government the power to snoop on others is an open invitation for them to snoop on us, and there goes our privacy. So let s pause and mull this one over. The drug war is blatantly unconstitutional. Stop the war and you stop the justification for spying. Wipe the slate clean of all victimless crimes and you stop most of the justification for spying.