I also thought of the comparison to “bird strikes”. But modern turbofan engines can take a hit — at least by a single bird — so I think a small X-wing quad copter would be similarly shrugged off.
The miracle on the Hudson River? There I think Sulzberger’s plane hit a flock of migrating birds. I may be wrong, but where ducks & geese are involved at that time of year you’re seldom looking at a single strike.
A quick search shows Virginia Tech has done some detailed simulations showing how an 8 lb drone can destroy a turbofan. They conclude that turbofans need to be redesigned to handle this risk!
https://www.uasvision.com/2015/11/09/drone-strikes-could-cause-jet-engine-failure/
Better story says FAA is using Virginia Tech to do the reseach and has two simulated videos of crashes of 8 lbs and 4 lbs drones into turbofans.
A deliberate attack on POTUS could easily employ a drone in excess of 8 lbs.