One night when we were in Saigon, it was so hot outside that we got lost on our way to dinner from the hotel—a fairly straight shot across the city, walking distance, in one of the more tourist-friendly districts where they have an ice cream parlor named “Fanny” and a variety of fluorescent-lit pho shops that are popular with locals, too. It is that hot outside now. I’ve lived here for 12 years and got lost trying to get to University and 13th Street. The damp makes everything feel like rust.