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PostNon-State Soldiers: Max Boot and Mao Zedong (Harry Papasotiriou, Greece, 09/28/19 4:28 am)
On non-state soldiers, Max Boot's Invisible Armies is a monumental recent historical survey. Mao Zedong (Tse Tung) has written very insightfully on guerrilla warfare and some of his texts are available online.
JE comments: Boot's book is described as the Clausewitz of the 21st century. Google it and see for yourself (!). My reading list just grew by one entry.
May I make a prediction? All warfare of the 21st century will involve an "invisible army" on at least one of the sides. When was the last old-school war involving two standing armies? Probably the US invasion of Iraq in 2003. The conventional phase lasted one month.