I'm not sure I'd consider a trap an "autonomous weapon". The trap cannot select a target. It will go off for anyone unlucky enough to step in its trigger.
An autonomous drone will select a target and pull the trigger. It fills in the position of a human pulling a trigger, which is a decision.
Maybe if robots began deciding where to lay mines, i could hand it to you.
I mean by some measure a trap can be worse, as many people have died from mines years after no conflict.
I'm not saying one is better or worse, just outlining the difference.
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