Isn’t the money used in Iraq American tax payers money?

From 2003 to 2005 America shipped literally 12 billion dollars in cash and this money was distributed or lost without any auditing.

My question is, is there anyone in government to hold accountable for such a waste of our monies? Isn’t there some sort of checks and balances for monies beyond congress?
This was largest payout in American history. This makes me sick. Check out democracynow.org