fire support assets, is combined with isolation of enemy forces and the exploitation by movement of enemy weaknesses. Bypassing and cutting off enemy strongpoints often results in the collapse of that strongpoint even where the physical damage is minimal, such as the Maginot Line. Firepower, primarily used to destroy as many enemy forces possible in attrition warfare, is used to suppress or destroy enemy positions at breakthrough points during maneuver warfare. Infiltration tactics, conventionally or with special forces, may be used extensively to cause chaos and confusion behind enemy lines. The retired officer and military theory author Robert Leonhard summarizes maneuver warfare theory as "preempt, dislocate, and disrupt" the enemy as alternatives to the destruction of enemy mass through attrition warfare. Since tempo and initiative are so critical to the success of maneuver warfare, command structures tend to be more decentralized with more tactical freedom given to lower-level unit leaders. Decentralized command structures allows "on the ground" unit leaders but still works within the guidelines of the commander's overall vision, to exploit enemy weaknesses as they become evident, which is also called "recon-pull" tactics or directive control. The war theorist Martin van Creveld identifies six main elements of maneuver warfare: Tempo: as illustrated by John Boyd's OODA loop. Schwerpunkt (focal point): the center of effort, or striking the enemy at the right place at the right time. According to van Creveld, ideally, a spot that is both vital and weakly defended. Surprise: Leaving the enemy unable to counter an action is central to any maneuver, and may be achieved by their remaining unaware for as long as possible Combined arms: the use of multiple means by which to attack the enemy creates an opportunity cost to any reaction. Should the enemy counter against one form of attack, they may leave themselves vulnerable to another. Additionally, different forms of attack may support each other through concurrent action (ex: Infantry supporting armor in such a way that the infantry has more available firepower, and the armor has protection from ambush) Flexibility: a military must be well rounded, self-contained and redundant. By maintaining different avenues of attack, either in method, movement, or any other factor, alternatives are always available, and opportunities can always be seized Decentralized command: rapidly changing situations may outpace the orders of a centralized command, leaving personnel with instructions that no longer apply. Lower levels of command must understand overall