Related Articles and Information: Visit OCA’s Organic Transitions Campaign page or our Breaking the Chains: Buy Local page.

If some sort of natural disaster or terrorist attack were to shut down New York City’s food supply chain, our supermarket shelves would reportedly be picked clean within three days. Other U.S. cities aren’t any better prepared for such emergencies, thanks to our fuelish dependence on a globalized food system.

So my husband Matt keeps a bin filled with tins of sardines under the bed in our sardine tin-sized Manhattan apartment. Plus two cans of organic vegetarian chili, and a Kelp Krunch sesame energy bar. He’s on a self-sufficiency kick, too; makes his own vanilla extract, sauerkraut, duck rillette, and cat food. I guess we’ll be in pretty good shape if calamity comes a-callin’.

But how will our fellow New Yorkers feed themselves? Will they pluck purslane from the sidewalk cracks? Raid Annie Novak’s rooftop farm? Where will the freegans forage when the dumpsters are as empty as a Palin stump speech?

Matt and I aren’t the only ones stewing about our far-flung food chain. Evan Fraser, co-author of the new book Empires of Food: Feast, Famine, and the Rise and Fall of Civilizations, declared on NPR’s All Things Considered recently that our entire future is imperiled by a global food system “built on some very, very rickety pillars.”

San Francisco city hall and lettucesLettuce lead the way: San Francisco planted a temporary Victory Garden in front of its city hall as part of 2008’s Slow Food Nation; the city has since enacted a regional food policy. Fraser warns that the U.S. is making the same agricultural missteps that brought down the Roman and Mayan Empires: degrading our topsoil; banking blindly on ever-higher yields at a time when unstable weather patterns and depleted resources will more likely bring reduced harvests; cultivating a monoculture that’s economically efficient but ecologically ruinous. And talk about a vicious cycle — our fossil fuel-intensive, forest-and-ocean-destroying farming methods worsen climate change, which makes it ever harder to grow food all over the world.