Apparently it wasn't Napoleon who said an army travels on its stomach. But surely the necessity of providing appropriate gear, food, water and other basics to troops was clear after his troops, freezing and dropping from starvation, staggered in retreat after the disastrous 1812 invasion of Russia. Of the 680,000 men Bonaparte took with him, fewer than 100,000 returned.

Perhaps nothing that dramatic is about to happen in Afghanistan. But the warning signs of impending trouble are clear: the $57 billion U.S. investment in Afghanistan's security forces is at risk because the Afghans cannot supply, or resupply their troops, can't prevent their weapons and vehicles from breaking down and can't fix them when they do.

And it's not clear that the 10,000 American troops President Obama has authorized to stay on the ground in Afghanistan can fix this against the deadline of steadily encroaching Taliban forces.

From what I've seen in Afghanistan, the men (and women) of the Afghan National Army and National Police are credible and often heroic fighters, especially given the circumstances of fighting for a distant government that pays only intermittent attention to their well-being.

Much of the failure lies instead with the Pentagon and its coalition partners in Afghanistan, who poured billions into buying fancy stuff for the Afghans "without building the entire end-to-end logistics system down to operational and tactical levels." That's the sorry admission contained in the Defense Department's most recent report on the state of the 13-year war in Afghanistan.

One result: Over the past 24 months the United States delivered tons of costly new equipment to the Afghan army's combat engineers. These are the folks who sniff out and disarm the roadside bombs, set by the Taliban, that disproportionately kill a growing number of Afghan civilians.

The Pentagon hired contractors to do the maintenance on the equipment. But the contracts ran out before the end of fiscal 2014, last October, and so did the contractors. Now, 80 percent of the new equipment is non-operational, according to a new report by the Defense Department's Inspector General, because no one's been around to maintain it.

For much of the past decade, the Pentagon insisted that the Afghan army's logistics be run from the top down. That is, Afghan officials and U.S. advisors in Kabul would tell units in the field what they needed and when they'd get it. Understandably this led to gigantic misallocation of equipment and supplies, with favored commanders being over-supplied and others shorted, without regard to the tempo of fighting. The Pentagon IG report doesn't mention corruption, but I suspect it played a role here, too.

But even if everyone was honest, there was no way field units could request supplies (ammunition, for instance) except by paper, which piled up unsorted in dusty offices in Kabul. This was because the computer system purchased for the Afghan defense ministry didn't work.

Out in the field, trucks and armored vehicles and weapons broke down or wore out and there were no spare parts, or mechanics, to fix them. Neither was there a process for turning in broken gear, so commanders would simply order new ones and leave the old broken stuff rusting out back. When the IG's gumshoes went to check out the problem they found units with 150 to 200 percent more vehicles than they were authorized because so many were broken.

The Afghan National Army central depot in Kabul was supposed to be the dazzling centerpiece of the army's new, western-style logistics system. Instead, the Pentagon IG found the U.S.-built facility "was not functioning effectively due to inadequate funds, limited space, missing equipment and lack of properly trained mechanics."

Some 200,000 weapons were missing from the central depot, according to an investigation by the U.S. Special Inspector General for Afghan Reconstruction.

Going forward, as they say here in Washington, things are likely to get worse for the Afghan troops battling the Taliban. The "transition" in Afghanistan from a U.S.-run war to an Afghan-run war has been the subject of intense debate for several years. But somehow, no one considered logistics.

Planning to train and install advisors and fix the logistics system problem never took place, according to the IG report. Looking at post-2014 Afghanistan, the IG wrote, this failure "increased the risk that U.S. funds will not be budgeted or spent effectively or responsibly by Afghan General Staff or Ministry of Defense officials."

Napoleon would get it.

Photo courtesy of Defense Department office of the Inspector General