Reminds me of the proposal to keep the nuclear launch codes inside the body of an innocent volunteer, so the President would have to kill the person to get the codes. https://boingboing.net/2015/12/11/proposal-keep-the-nuclear-...
If you believe we should never use nuclear weapons, then don't have them at all.
If you believe there is a case where it may be moral and rational to use nuclear weapons, why would you want to put a potential barrier in the way of their use? You could have a situation where everyone was agreed to use them but the president was physically unable to harm the aide to use them.
You can know that something is the right thing to do but not have the courage to physically harm someone to do it.
An interlock that you may not be able to unlock for reasons unrelated to the task at hand is a bad interlock.