The U.S. military is good at fighting wars, but it sucks at managing money. Partly because of its convoluted bookkeeping systems, $8.5 trillion—yes, trillion—taxpayer dollars doled out by Congress since 1996 has never been accounted for.

That was also the first year that Congress passed a law requiring the Defense Department to be audited, which it has failed to do. In 2009, Congress passed another law requiring the DOD to be audit-ready by 2017. After spending—no wasting—billions on failed accounting software, the department is likely to miss that deadline, too.

Related: How the Pentagon Cooks the Books to Hide Massive Waste

So how does the military handle their books for the U.S. Treasury department? They cheat.

A scathing investigative report by Reuters in November 2013 described how an accountant at DOD in Cleveland would face the same monthly problem: Missing numbers, wrong numbers -- numbers with no explanation of where they came from or what they were for. To rectify the problem, the accountant was instructed to “plug” in false numbers in the DOD’s books.

How can an agency known for superior strategic planning on the battlefield be so incompetent on the home front? Is it arrogance? Sloppiness? Or simply a misplaced disregard for what their lack of discipline is costing the country.

As Reuters reported, a 14-year supply or 15,000 "vehicular control arms" of the military's Humvees were in stock as of November 2008. Yet, from 2010 through 2012, the agency bought 7,437 more of them -- at prices considerably higher than it paid for the thousands sitting on its shelves.

More recently, we have sadly reported just a few of the mounting accounting problems at the Pentagon:

What should Congress do? Continue to blithely increase the defense budget when the department can’t handle money? Call in Ernst and Young to do it for them? Or simply tell them they won’t get another red cent until they figure out how to add and subtract.

At a time when the country is facing entitlement cuts and desperately trying to not just repair but invest in new state of the art infrastructure, shouldn’t the agency with the largest federal budget justify what it spends and why? At the very least, if DOD doesn’t pass an audit, it should be penalized—just like you and me.

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