A longtime friend of this magazine, John Margolies, has spent the last quarter-century photographing America’s vanishing roadside architecture. He was among the first to find enduring appeal in mom-and-pop tourist cabins, concessions shaped like hot dogs, and gas stations ornamented with a windmill or a B-17. Now the U.S. State Department has organized an exhibit of 56 of Margolies’s pictures, which will tour through the end of 2006, appearing n museums and cultural centers in Europe, Asia, the Middle East, and Africa. (Last month the show opened in Kiev, Ukraine; Ankara, Turkey; Vientiane, Laos; Maputo, Mozambique; and Kuwait City.) What message does the government hope to convey with these photographs of one-off homegrown design? “As cars became affordable for millions of people,” reads the exhibition brochure, “… the American free enterprise system responded….”