I&#x27;m going to have to dispute that one... an implosion weapon is <i>very</i> complicated. Even if you had detailed plans, you simply can&#x27;t build them without access to very high precision tools. The tolerances necessary to make them work are extremely severe, especially in the construction of the initiator (the thing that initially injects neutrons to kick off the reaction) and in the triggering for the explosives. The basic concept is really easy to grasp, but the nitty-gritty engineering details are much harder than is readily apparent.<p>Gun-assembled weapons are simpler, but still complicated. The big issue with them is that they tend to go critical as the target and projectile are coming together and blow themselves apart before the bang really gets going. Getting them to come fully together and stay confined long enough to get good yield is not as easy.