The article provides a description of the military evolution of the XIX-XXI centuries. The development of the operational forms and organizational principles are on focus. October war of 1973 and the American invasion of Iraq in 2003 prove the new principle of deployment of troops. A continuous strategic front is no longer the predominant principle of deployment in the theater of operations. Although war had rose to a higher level of scientific and technological development, modern organizational and operational forms are increasingly reminiscent of the local conflicts of the XIX century.