The twentieth and twenty first centuries have seen many advances in the technology and doctrine of warfare. A full listing of all these advances would only serve to make me cry, but in general, after stripping away all the flash and blood, their has been two switches in doctrine between the 19th century fixed line nation state warfare, and the 20th centuries warfare. And while these ideas are very new, there actual genesis is in some fairly ancient traditions that are not immediately related to warfare.
The two major advances in warfare are blitzkrieg, the lightning like war first used in World War II by the Nazis, and later used by the Israeli Defense Force in their wars, by the Soviets to crush resistance in Czechoslovakia and Hungary and by the United States in Iraq on two different occasions. Although Blitzkrieg was originally a tank centered doctrine, much of it is now applied with massive airpower. The idea of blitzkrieg is a massive wall of iron that moves deeply without thought for risks.
The second concept that changed warfare was the practice of large scale guerilla warfare by Mao Zedong and Zhou Enlai in China, and by Ho Chi Minh in Vietnam. While guerilla warfare in the sense of small commando raids had long been a part of war, the type of war practiced by the Chinese and Vietcong was quite different, because it led to the idea of mobilizing the entire population to fight as an army. While tactics like these have been employed in other areas, such as Africa and South America, they are not guerilla warfare in the same sense, because they are not mobilizing the entire population.
These two styles of war are very different, and one of the differences may come from the very different sources they come from, which is a rather odd story.
While Blitzkrieg was first introduced full scale in World War II, it was actually theorized starting in World War I by one General JFC Fuller. Fuller was, to say the least, eccentric. Before joining the experimental British tank corps, he was an acolyte of Aleister Crowley and a top lieutenant in the Ordo Templi Orientalis. After the war, he made a general drift into facism, later joining the British Union of Fascists. It could be said that Fuller's interests in politics and the occult had no more influence on his opinions on warfare than J Edgar Hoover's interest in women's fashions had on his criminology. However, a case could be made that blitzkrieg shows a rather hermetic worldview.
The basic idea of low hermeticism, such as that espoused by the OTO, is that the world is an irrational, chaotic place. The only way that this world can be controlled is by using a variety of forces that are outside of normal understanding, controlled by a person who has some kind of mysterious knowledge that helps him transcend the chaos and illusion around him. This is the basic idea of blitzkrieg, where the world is full of unknowable forces (the chaos of the battlefield) that can only be overcome by someone possessing the mysterious forces outside of normal comprehension (the technologically sophisticated means of protection and destruction that can totally overwhelm unequipped human flesh) and the will to use them. It should be no surprise that some of the greatest proponents of the wall of iron philosophy have been people who either irrationally (the Nazis) or rationally (the Israelis) believed that they were cut apart from the rest of humanity, and could only deal with it through use of almost magical forces.
Of course, what this view forgets is the maxim that war is the continuation of politics by other means. That is, war, no matter how irrational it seems at the time, usually has a reason behind it. That is why many blitzkreiging powers either don't care about administering their conquored territory, or when they do administer it, end up falling to guerilla warfare.
Guerilla warfare was developed by the Communist Party, people who were supposedly against the teachings of Confucius, but people who were well informed with them nonetheless. While there are many teachings associated with Confucianism, it could be easily said that Confucianism teaches that warfare is an epiphenomena of a nation's political strength, and that political stregth is an epiphenomena of a nations cultural and social status. So the Communists knew that in the end, their goal was to run society in a certain way, and they started to infuse these values into their army even before they went to war. They instructed their army, and their non-combatants, in such areas as ideology, physical training and iron discipline, and thus, when they went to war, they had the support of their society behind them, a support that eventually allowed them to swamp the Guomintang Armies. Thus they fulfilled what is written in Mencius: "an army that has the support of the people can win a war, even if it is armed with sticks and stones".
Thus these two different type of modern warfare come from two different, even contradictory paradigms: first, that to survive means controlling overwhelming, "magical" forces; and the second, that by controlling "knowable" and "everyday" forces on a large scale, you can eventually create a broad groundswell that is hard to put down.
Note that I make no judgements on which of these two paradigms is more militarily efficient or less morally reprehensible.