[Image: Russian troops in Grozny, February 2000; image courtesy of AP].

?U.S. land forces will eventually find themselves locked in fights within huge, dense urban environments where skyscrapers tower over enormous shanty towns, and these troops need more realistic training to operate within these future megacities,? Brigadier General Julian Alford of the U.S. Marine Corps Warfighting Laboratory explained earlier this month, as reported by Defense News.

It's war in the age of megacities: ?We talk about the three-block war, but we are moving quickly to the four-floor war,? Alford adds. We are going to be on the top floor of a skyscraper... evacuating civilians and helping people. The middle floor, we might be detaining really bad people that we?ve caught. On the first floor we will be down there killing them. ...At the same time they will be getting away through the subway or subterrain. How do we train to fight that" Because it is coming, that fight right there is coming I do believe with all my heart.The verticalization of Alford's metaphor??the four-floor war??is an interesting revision of the existing ?three-block war? paradigm. In that earlier version, U.S. General Charles C. Krulak suggested that three separate and very different military goals?humanitarian assistance, peace-keeping, and ?traditional warfighting??could all occur within only three blocks of one another in the urban combat of the future. In his words, soldiers would be confronted by ?the entire ...