The small weaponized drones do not fly 250 km/h.
Yes, but they still approach in just a few seconds.
They can fly at 350kph, check this redbull drone that was used in Olympics, acceleration of 100-300kph in just two seconds faster than any F1 car. Now add a bit of payload and you get the 200-250 speed range, still crazy fast.
https://www.redbull.com/id-id/worlds-fastest-filming-drone-b...