We managed to slow down the escalation of Iran/Israel at least.

It’s not that we haven’t solved the problem per se. It’s that the problem is unsolvable. With enough time and effort, anyone can make an atomic weapon.

But nuclear nonproliferation can only work if countries trust each other, but that trust has been broken for decades, maybe centuries. The fundamental trust issue is likely unsolvable, so everyone wants a bomb of their own.

In the absence of a perfect solution, slowing things down is our next best bet.