From readers.

• Position: Brief Article - Letter to the Editor

Where the Culture of Violence Is

In his essay "Lessons of Afghanistan: Understanding the Conditions That Give Rise to Extremism" (March/April), Michael Renner lists the dangers of "social humiliation and hopelessness created by a severe lack of education and job opportunities"; "a culture of violence (that) makes reliance on force generally more acceptable"; and "the widespread and easy availability of arms." How unfortunate that these conditions so aptly apply to my own country, where poverty and inequality remain largely unaddressed, and a culture of violence thrives. Though the article focuses on extremism across the waters, Renner's conclusion rings true here as well: "Unless our priorities change, [the costs of failing to advance human security...] are certain to keep rising in the years to come."

VALESKA POPULOH

American Farmland Trust

Washington, DC

At Least the Cows Don't Drive SUVs

Richard H. Schwartz points out the dangers a mushrooming farm animal population holds for us, and suggests that animal-based diets are a threat in this time of scarcity ("From Readers," May/June).

Let's say we have an island (our planet) with 100 acres of land that are usable for food production. An acre of agriculture can support about 10 times as many people as an acre for farm animals. If the inhabitants of this island are vegetarians, the maximum human population on the island is much higher. However, if they are meat eaters, then the maximum human population on the island is much smaller, because eating animals takes more land than it does to eat plants.

The question I would ask is, Do we really want to raise the maximum possible human population on our planet? While farm animals are terrible for the environment, they are nothing compared to the modern human being ("cows don't drive SUVs"). I'd rather have 6 billion people and 45 billion farm animals than the reverse.

JADE RUBICK

Portland, Oregon

Is that the only choice? How about, say, 4 billion people (eventually) and no farm animals? How about large, road-less tracts of wild land where people who still want to eat meat are free to go hunting for wild game on foot?

ZPG Is Not a Black Hole!

In an article about declining birthrates in the developed world, a foreign correspondent for The New York Times recently warned of "the demographic black hole of zero population growth." Black holes are the universe s gravitational traps from which not even light can emerge. That's a bleak outlook for folks in...