[Drango]

...have security patrolling the skies around major assets, not just refineries, and blast the drones

With shotgun shells or an Anti-Aircraft Battery? Trying to understand the technology you are proposing for the "blasting".

[null and void]

Current technology includes jamming the control signals, jamming or spoofing GPS/GLONASS signals, and hammering them with acoustic noise to destabilize the accelerometers used for inertial navigation.

There are probably a half dozen more I don’t know about...

[OrangeHoof]

I was thinking of surface-to-air missiles. They’re unmanned so you don’t need to worry about killing any pilots. And the perimeter should not be right at the facility so whatever payload they have lands away from assets or civilization.