Two tragic accidents in New York City this week highlighted what strikes me as a recurring tension in American culture.

In the first, a real estate executive was killed while rowing on the Harlem River. His scull was hit by a powerboat in the early morning light. The victim, 41-year-old Jim Rumsdorf, was probably hit head on by the powerboat. The other three rowers managed to swim to safety.

In the second accident, Newsweek editor Tom Masland was mowed down by a woman driving a 300-horsepower Volkswagen SUV as he crossed West End Avenue at 95th Street (quite close to where I live). The 55-year-old, married father of three died soon after.

One person rowing, one person walking, were killed by one person zipping along in a speedboat, by one person zipping along in a luxury SUV. Sane, solitary pleasures versus selfish ones. Two pursuits that suggest some harmony with the environment versus two that, in these days of dwindling oil, are increasingly hard to justify.

New York is a tough place for people who want to live a simpler life. (I wouldn’t ride a bike on the streets here if you gave it to me.) But why is it that you never hear of a walker or a rower or a cyclist killing a speedboater or motorcyclist or SUV driver? And how come no one ever seems to care?