Traveling across the United States, it's easy to see why Americans are often thought of as stupid. At the San Diego Zoo, right near the primate habitats, there's a display featuring half a dozen life-size gorillas made out of bronze. Posted nearby is a sign reading CAUTION: GORILLA STATUES MAY BE HOT. Everywhere you turn, the obvious is being stated. CANNON MAY BE LOUD. MOVING SIDEWALK IS ABOUT TO END. To people who don't run around suing one another, such signs suggest a crippling lack of intelligence.