The world is "lucky" that the US had the first A-bomb.
If the Germans had it first, we'd all be speaking german.
If the Russians had it first, we'd all be speaking russian.
If Israel didn't have nukes, they wouldn't exist.
China has nukes - I think they see them mainly as a defensive weapon, and as a source of world prestige and power.
India and Pakistan nukes have probably prevented all out war between them.
Why does N. Korea need nukes? They can't even feed their own people. They only want them to threaten others.
Why does Iran want nukes? They're nuts!
If I recall, the No Nukes protest movements came from those who believe we never could or should defeat the Soviet Union, that we would have to accept the USSR as a Communist entity.