At the end of the twentieth century, during operations in the Persian Gulf and other remote parts of the planet, American military strategists developed the concept of “fourth generation warfare.” In our time, such warfare has become a global standard, which is rapidly expanding thanks to new and returning old players in the international arena and the emergence of new methods of destroying the enemy: combat drones, supersonic missiles, etc. The position of light infantry has also changed in modern warfare. Now it ranks second after aviation on the battlefield. This has been demonstrated repeatedly in Iraq, Afghanistan, Syria, and now in the conflict in Ukraine. The book describes in detail the tactics of light infantry in modern warfare, and also provides explanations of the reasons for the defeat of the United States in some modern wars (including in Afghanistan in 2021).