Copulaters, start your engines. In Saturday's essay in The Wall Street Journal, author Jonathan V. Last makes the case that the nation's dropping 1.6 fertility rate (it's 1.54 in China, where there's a strict one child policy) is America's biggest problem. "Once a country's fertility rate falls consistently below replacement, its age profile begins to shift. You get more old people than young people," Last writes. "And eventually, as the bloated cohort of old people dies off, population begins to contract." Last argues that contrary to popular belief, growing populations actually lead to "increased growth and conservation."