The vertical battlefield.(Complete Guide)

"The worst policy is to attack cities ... attack cities only when there is no alternative." wrote Sun Tzu in his Art of War (c. 500 BC). He was correct: urban fighting involves challenges and costs that can far exceed those of conventional warfare. The effectiveness of superior weapons and communications technology is blunted in the urban environment, but new tactics, training and equipment are being developed to try to overcome these disadvantages.

Armies fight in cities not because they want to, but because they have to. Population, especially in the developing world,