AFP / Getty Images The new $750 million U.S. embassy complex in Baghdad, under construction.

Seems that while pretty much all U.S. troops have marched out of Iraq, U.S. greenbacks continue to march in – in massed formations.

This was made clear Tuesday when the Government Accountability Office made public its recent ruling on a bid protest by one contractor, Exelis Systems Corporation, of Colorado Springs, Colo., against the State Department. Exelis, until two years ago a part of ITT, contended the government improperly awarded a contract “for operations and maintenance support services (OMSS) for agency facilities in Iraq, including the Baghdad Embassy Compound (BEC)” to PAE Government Services, Inc., of Arlington, Va., once part of Lockheed Martin.

The legal mumbo-jumbo will interest only lawyers, accountants and other no-value-added ne’er-do-wells, but the contract’s bottom line should be of interest to taxpayers:

$2,000,000,000.

That’s a million dollars a day over a five-year period, if the contract hits its ceiling. The down payment is $347,883,498 (don’t you just love such precision? It’s almost a prime number, for Pete’s sake).

No wonder a private-equity company bought PAE from Lockmart two years ago. Check out this photo essay to get a sense why its upkeep is so costly.

It’s actually the second time Exelis protested the government’s decision regarding this contract.

The original protest ruling, issued last fall, said Exelis was right to gripe, and urged the State Department to reopen the bidding. State reawarded the contract to PAE, which led to Exelis’ second protest.

In Tuesday’s decision, the GAO sustained only one of Exelis’ several points, but recommended nonetheless that the State Department reconsider its decision before signing that contract with PAE.

Read these decisions, if you dare. Such contracting disputes are so mind-numbing, the legal work involved must pay a lot.