I associate the ballon with today's killer drone. Its task is to control or kill the targets. It's a natural "futuristic" tool that is an integral part of the surveillance system, the "All SEEING EYE". The EYE is the equivalent of what we see today with the security cameras and all the other gadgets that spy on us. Monitoring is one function but then you also need a tool to physically influence those being observed, that is the balloon/drone's function.
Quite clever that something like this was chosen, as the then sci-fi movies already had robots. So choosing a balloon is a highly creative choice for such a function.