Have the marines become too big for today? Intruding in Army territory such as Afghanistan?

In reality the Marines are just light infantry. I don't mean "just" or "light" in any sort of negative way whatsoever. They are the best light infantry in the world. Light infantry has all sorts of responsibilities most notably establishing a base of operations in an enemy occupied area. The Army doesn't do that they take over the base after the Marines establish it or operate in a FOB behind the foremost Marine units. Traditionally the establishment of such forward areas was by taking a place from a beach head.Well with landlocked countries that isn't a relevant fact but the mission remains the same and the Marines do it quite well. We are still very much a country at war and every service member (especially a Marine) wants to do what the mission to calls for and that's exactly what is happening now. The Marines aren't too big they are the smallest branch of the major 4 branches of the military.