The reason that the branches of the military don't get along with each other is a simple language barrier.

If you tell the Marines to secure a building, they will go in with a full tactical assault team, kill everyone inside, and fire defensive fire at anyone who approaches.

If you tell the Army to secure a building, they will set up barricades and not allow anyone in or out of the building.

If you tell the Navy to secure a building, they will lock all the doors, turn off the lights, and leave.

If you tell the Air Force to secure a building, they will sign a three year lease with an option to buy.