America isn't running out of everything just because of a supply-chain crisis. America is running out of everything because Americans are buying so much stuff.

• Disruptions in global supply chains have generated the phrase "everything shortage."

• But US imports are at record levels at some ports, and Americans are breaking shopping records, too.

• Supply-chain professionals plan to alleviate the backlog container by container.

Americans are buying everything they can get their hands on, and they'd be buying even more if it weren't for those pesky supply-chain snarls, the National Retail Federation said.

"Spending might have been higher if not for shortages of items consumers are eager to purchase," Jack Kleinhenz, the NRF's chief economist, said in a statement issued on Friday.

Those shortages seem so ubiquitous that the term "everything shortage" is now being used liberally to describe consumers' frustration as they try to get goods of all sorts: paper towels, milk, toys, and more.

Yet claims that the country is running short on everything miss a key point. America has, in fact, imported an immense amount of stuff in the past eight months. And that's part of the reason we're in the midst of an epic supply-chain congestion.

Video: Where 6 things go after they're discarded

We imported more stuff ... then we bought it

To understand the situation, consider the country's inventory to sales ratio. This metric, tracked by the US Census Bureau, compares how much stuff sellers have on hand to how much stuff consumers are buying. The ratio is at a 10-year low, which indicates that we're low on stuff.

But the Port of Los Angeles reported a 30% uptick in incoming cargo in the first nine months of this year. (Important note, most of nonfood goods sold in the US come from abroad.) The Port of Charleston, South Carolina, has been breaking all-time records since March. Prologis, a major industrial real-estate player, is "effectively sold out" of warehouse space.

All of that means that the inventory to sales ratio isn't low because the US is short on stuff. It's low because sales have gone completely nuts.