Doesn't really matter, though. If you have to build your tools up from that level, it's going to cost so much that only governments and huge corporations can do it--and those are exactly the people installing the backdoors in the first place, so we're back to square one.
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I'm not sure how you put a backdoor in an atom.
Easy: You put the backdoor into the atoms it's entangled with.
Doesn't really matter, though. If you have to build your tools up from that level, it's going to cost so much that only governments and huge corporations can do it--and those are exactly the people installing the backdoors in the first place, so we're back to square one.