Walk into an H&M, Zara, Forever 21, or any other fast-fashion outlet and you'll see it: people throwing bargain-priced jeggings, peacoats, and clingy tank tops into their carts as if they were buying staples at the supermarket. Shoppers with stodgier tastes do the same with $12 capris at Walmart and $20 blazers at Kmart. In 1985, Americans on average bought 31 items of clothing a year. Today, we buy roughly 60—more than one per week. And when we lug home our haul we're not shy about making room in the closet: We throw out 78 pounds (PDF) of textiles per person—five times as much as we did in 1970.
What gives? It isn't like we have more cash to burn—US median incomes have stagnated over the same period that our clothing habit has exploded. What's happened is clothes have gotten cheaper. Starting in the early 1990s, US clothing prices began a steady decline (before picking up a bit during the Great Recession), driven down by cheap imports from Asian clothing factories that were fed a steady supply of ever-cheaper cotton.
As food prices hover near all-time highs and millions go hungry, the biofuel boom has gotten much of the blame. But what about our hunger for cotton? Nearly half our clothes are made of the fluffy fiber, and around 2 percent (PDF) of cropland worldwide is devoted to it. That might not sound like much—but consider that cotton is the thirstiest crop in the world. And it commands fully 16 percent (PDF) of the insecticides consumed each year, more than any other single agricultural product.