Runaway Spending on War Contractors
War especially privatised war looks profitable; for various reasons the US military and executive branch has sought to disguise troop numbers and outright cost of its conflicts and wars by the simple expedient of paying privateers, mercenaries, to conduct security operations on their behalf.
The troops might come home but the mercenaries and their fees will stay and probably increase. Understand this and you begin to understand the loss of power suffered by congress and constitutional government.
At what cost armed forces beyond the control of Congress?