Let's imagine that tomorrow we (well, only those 18 or older, so not me) all wake up and find a nuclear bomb next to our bedsides1. The bombs are about the sizes of hand grenades2 and are easy to transport3. Each person can only set off their own nuclear bomb.
Once society adjusts to this fact, things will change, and change quickly. For example, wars will suddenly be much different, given that each side can blow up quite a lot of things.
How will wars be fought if everyone gets such a hand grenade?
We have to ignore the obvious, which is that some madman will set off his/her nuclear weapon rather quickly. Let's assume that something like that doesn't happen.
The yield of each weapon is about 10 tons of TNT.4
1 Very unlikely.
2 Also unlikely.
3 Still unlikely.
4 The unlikeliest of them all.