Costco Membership Card Is Not a Replacement for Real ID

Eagerly anticipating the article in some fru-fru travel blog, "Man travels 28 countries with nothing but his passport and Cosco ID."

"It's a livesaver," the traveler gushed, "Never leave home without it."

You don't actually need an ID to fly. I lost my passport in Mexico last year. I re-entered the country on a ski pass.