Large-scale atomic warfare has to be one of the daftest ideas. M.A.D. or mutually-assured destruction is plain nuts. A not-so-daft idea is a universal disarmament or drastically reducing the world’s stockpile of nuclear weapons.
What about small-scale atomic warfare, i.e the use of tactical nuclear weapons? Is this acceptable in certain situations? To end World War II, President Harry S. Truman had to make the extremely difficult decision to use 2 atomic bombs to end the war which would otherwise have claimed even more lives, American and Japanese.
Perhaps retaining some nuclear weapons in the probably unlikely event of an alien invasion would be a good idea if you believe our atomic weaponry to be any match for an alien arsenal.