The ones we use to spy on people and shoot small missiles are slow, but they are designed to stay in the air for a very long time. I assume they make drones to

The ones we use to spy on people and shoot small missiles are slow, but they are designed to stay in the air for a very long time. I assume they make drones today that are much faster (hypersonic missiles are very drone-like in some ways), we just don't know about them yet.