GPS coordinates covering the volume of the air,

as in, from ground level to the atmosphere,

will place mobile anti-missile system in

arrangement and formation of choosing.

Whereas sensors will replace what will

be down from impact. So imagine

a giant 'cube' surrounding a city,

in times of peril.

And these drones would be in storage

nearby the city. Distance from the city,

between the drones, layering formation,

would differ.....