How and why have weapons changed?

All weapons are simply ways to concentrate force. A club uses leverage to concentrate force, a knife uses a wedge (the blade). Over time, the amount of force able to be concentrated has steadily grown. The English longbow changed warfare forever by allowing more force to be stored than ever before. That was the last major innovation using just muscle power. Then there was a sea change--chemistry was added into the mix, allowing bombs and guns. The force one man could employ wasn't limited in any way to his muscles. Now we have atom bombs, which concentrate incredible force into an area about the size of a basketball. But the fundamental aspect of weaponry--applied force--hasn't changed yet.