I would like to revisit the trolley problem. A trolley on a track is out of control and headed to a place where the crash will kill 4 people. You can flip a switch and put it on a different track where the crash will kill only one person. Should you flip the switch?
It appears to be the consensus of poskim that you should not. It is not up to you to decide who lives and who dies, even in a one-life-versus-many situation.
I am not convinced this is the absolute rule and the final word. What if the trolley carries nuclear weapons and is headed for the heart of New York City, and you can redirect it to a place where far, far fewer people will die in the crash? (We are not talking war or terrorism here, only accidents.) Is this discussed anywhere? Judaism does not teach us to apply rules blindly.