When I get on a bus with other people, I can, with a fairly high degree of certainty, rest assured that the other passengers will not just randomly kill me to get something from me. That's because the people, just like me, have some level of comfort and their basic needs being met.

The further we slide away from that, the higher the risk for everyone. And to maintain that needs constant work, from everyone.

How about dropping a rock from a drone so it isn't up close and personal.

The difficulty for an attacker is the explosive payload, not the delivery mechanism. If it were easy for an attacker to get an explosive payload there would be car bombs going off every day as an easier delivery mechanism than use of quadcopters.

Thankfully it seems to be relatively easy to prevent people from making explosives, at least outside of warzones in countries with strict border control, because random people don't have a valid reason to buy industrial chemicals or equipment, and especially not chemicals identified as precursors for making explosive compounds. And for plants where such industrial chemicals are legitimately necessary to use, inputs and outputs can be measured, and detection taggants[1] used, and many other security measures, to prevent accidental or deliberate loss of control over such chemicals.

[1] https://en.wikipedia.org/wiki/Taggant#Explosive_taggants

I do think that war would be better off being done remotely via automated floating and aerial weapons platforms controlled remotely if not semi-autonomously. I mean without soldiers on the front line.