A M18 claymore mine only weighs 3.5 lbs. A couple of these mounted to a drone frame, pre-program the flight path, fly it low and between the trees, have it come up on an outdoor gathering, fly up to 100 feet before it is fired. Could cause quite a bit of damage. Of course, getting hold of a claymore mine is a bit of a problem for most people.
I’m not even sure how you would be able to detect and/or defend against such an attack.
Build a massive tennis court screen enclosure over the WH grounds...
I don’t know, but if one of those can get there to the WH and can carry that much...it’s a problem.