You can use the Air Force to hold land. That is what tactical bombers are designed for. Just ask the Germans who were in Normandy. Ask the French in 1940. Ask the Greeks during 1941. If you don't have air superiority, you cannot control or hold positions. Basic warfare tactics.

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"They wrote in the old days that it is sweet and fitting to die for one's country. But in modern war there is nothing sweet or fitting in your dying. You will die like a dog for no good reason."