KABUL, Afghanistan—I was the youngest person on this pendulum ride at the city zoo by about 35 years (no exaggeration). There is a small "ferris wheel" to the left. Most public space is decidedly masculine and the ratio of boys to girls at the zoo on Friday, the Islamic day of public prayer, was least 10-to-1. Even still, the zoo is one of the few spaces in which boy and girl mix at all, university students tell me. Afghanistan is a young country, with more than half the population of some 30 million under the age of 19.