What is so difficult about developing nuclear weapons that makes some countries incapable of making them?

Question

What is so difficult about developing nuclear weapons that makes some countries incapable of making them?

In: 1394

Answer 1

To add to other people’s comments: Small countries also have a limited number of scientists and engineers that they can afford to employ and maintain. So putting many of those scientists and engineers on the nuclear weapon project takes them away from other things the country may need; like roads, bridges, power plants, vehicle design and construction and everything else that a country needs in order to function.