Will military drones eventually be as small as a hummingbird?

The challenge isn't making something that small—it's making it useful.

A hummingbird-sized drone would need to solve several difficult engineering problems:

• Power: Tiny batteries store very little energy.
• Communication: Small antennas have limited range and bandwidth.
• Computing: Fitting advanced autonomy into a tiny airframe remains difficult.
• Weather: A 20 mph wind that barely affects a larger drone can completely overwhelm a hummingbird-sized one.
• Sensors: Miniaturizing high-quality cameras, infrared sensors, and other equipment without sacrificing performance is challenging.