The current DAIM AIs do not develop nukes. We decided against it because the somewhat random AI usage of these assets doesn't justify the considerable investments necessary in our opinion - e.g. the AI doesn't care about occupied provinces and the US might simply nuke Paris or an occupied England when they feel like it.
We might change that a little for the next version though. I think about giving the US at least a chance to start developping nukes, same for a successful Germany.