by MATTHEW GAULT

Since 2002, Congress has set aside $104 billion specifically to rebuild Afghanistan. Of that, $66 billion went to the Pentagon.

Recently, the Special Inspector General for Afghanistan Reconstruction asked the military to account for all that spending. It couldn’t. According to a new report from SIGAR, the Pentagon only knows how it spent a third of its reconstruction budget.

That’s $45 billion dollars the military can’t track and the reason is … ridiculous. According to SIGAR, the Pentagon didn’t check a box on an electronic form when it filed the information in government databases.

It didn’t break any rules when it did this, and has since fixed the oversight that led to the underreporting, but it’s cold comfort for taxpayers who will probably never know how the U.S. military spent that money in Afghanistan.

Most likely … not all of it well. The Pentagon has a history of wasting billions in the country on bad projects, corrupt business partners and disreputable construction companies.

In Feb. 2013, SIGAR began to audit all the cash the U.S. military and other agencies were spending in Afghanistan. The watchdog wanted records about grants, contracts and any other agreement where money changed hands.

Two months later, the Pentagon delivered a report that accounted for a little more than $23 billion out of $66 billion. SIGAR was confused. “Obligations for the Afghan Security Forces alone totaled $44 billion,” SIGAR wrote in a March 2014 followup letter to then-Secretary of Defense Chuck Hagel.

The letter, obtained by War Is Boring, explained that SIGAR can’t do its job — detect waste, fraud and abuse — if it doesn’t have all the information.

“We have attempted to reconcile the identified discrepancy in the data provided and have been unsuccessful in accounting for this sizable gap with [the Pentagon],” SIGAR added in the letter.

Then the watchdog asked for the records — all the records — a second time. But the Pentagon didn’t provide the information, and argued that pulling records for the unaccounted $45 billion wasn’t feasible.