text: can japan have nuclear weapons? a friend of mine said that when japan surrendered at the end of ww2 part of the treaty was they could never have a military or have weapons to the extent to never be a threat to the united states again. is this true? actually the japanese announced today they are in fact capable of building a nuclear weapon. they have many limits on their military capabilities, but they do have the technology should the need arise.    considering n. korea's recent actions, they just might break some of treaties they feel they need to, in order to protect themselves.