Nuclear Weapons.

Don't know how to answer to the big question, but I could not hesitate to link as flavour pic to the discussion a pic about "rope trick effect", where the explosion shockwave runs faster in the cables holding the device than in air.

 

 

it was more elaborate than that-the weapons actually kept two mostly rational nations from going to war. during the cold war, there were representational fights and small wars, but the thing keeping the usa and the ussr from launching into a huge full blown death and destrction war was the fact that neither wanted to be the one that set forth the wheels of annihilation. the problem with nuclear weapons in the hands of religious radicals such as iran or rogue nations such as north korea (they are a chinese puppet that is now refusing to listen to china) is they are more interested in wreaking havoc than in using diplomacy to avoid war. iran is without a doubt the biggest factor in the terrorism being carried out in the middle east. they would have no qualms turning over nuclear warheads to hamas or hezbollah to cause mayhem. similarly, north korea could hand over nuclear weapons to enemies of the usa, europe or even china to prove a point and to get funding.