> It's an awesome engineering project whose purpose is to kill tens of millions of people.

And your alternative is ....

> This stuff has been technical catnip to several generations of scientists and engineers, but I think it's perfectly legitimate to step back and consider the moral element

Yes, let's consider the moral element. You clearly think that this was wrong, so what was correct?

Note that these weapons worked exactly as intended. They were never used. Your alternative has to do at least as well.