Cindy McCain has four children, including a daughter adopted from Bangladesh. Michelle Obama has two school-age daughters.
Alaska Gov. Sarah Palin has five children, including an infant son with Down syndrome. Jill Biden raised a daughter to adulthood, as well as Sen. Joseph R. Biden Jr.'s two sons, who lost their mother in an automobile accident when they were young.
It is unlikely these women were weakened by motherhood.
But the elevation of Mrs. Palin to Republican vice-presidential nominee has produced more than a little clucking in the media about whether she can do the job while she has children at home.
Oddly, the other wives were not targeted this way. Maybe it's because they will have "light duty" as first or second ladies of the nation. Or maybe they fit the media's mold for working mothers, whereas Mrs. Palin smashes it.
I would like to reference the work of a journalist whose political views are unknown to me but who doesn't doubt, at least in theory, that Mrs. Palin - and Mrs. McCain, Mrs. Obama and Mrs. Biden - can rise to the tasks that come before them.
Motherhood sharpens the mind, Pulitzer-Prize-winning investigative journalist Katherine Ellison concluded in her 2005 book "The Mommy Brain: How Motherhood Makes Us Smarter."
According to research, mothers are likely to be exceptionally resourceful problem-solvers. They're "looking out not just for No.1, but for Nos. 2, 3, 4 and so forth," Mrs. Ellison once told me.
Mothers are also likely to have heightened sensitivities to people's needs and all kinds of smells, sights, sounds and movements. "Mom radar" is how Mrs. Ellison puts it.
So why do some people think motherhood turns women into ditzes who can't speak a coherent sentence or remember anything for more than two days?
It's because pregnancy and (sleep-deprived) new motherhood do affect women's brains - in fact, women's brains shrink slightly during and after pregnancy. This apparently leads to a deterioration in concentration, memory and expressive language skills.
But a few months after birth, women's brains not only regain their normal size, they return with a greater capacity for performance, social skills and emotional intelligence.
The female brain is almost remodeled, neuroscientist Craig Howard Kinsley said in a 2006 article on "The Maternal Brain" in Scientific American magazine. His studies comparing "virgin" rats with mother rats show that the mothers are better at foraging for food, finding their ways through mazes, building nests and protecting young rats from predators. "What is more, the cognitive benefits appear to be long-lasting, persisting until the mother rats enter old age," Mr. Kinsley wrote.
I recently checked with Mrs. Ellison (www.themommybrain.com) to see what she says today about mothers' brains.
"The job of a mother can resemble that of a CEO, with multiple and varied responsibilities, a great need for flexibility, and coolness under pressure and other dimensions of emotional intelligence," she said.
Does motherhood automatically turns every woman into a focused, resourceful strategic planner? No.
Are women who don't have children less qualified for public leadership? No.
But for most women, motherhood appears to be one of their greatest assets.
• Cheryl Wetzstein's On the Family appears Tuesdays and Sundays. She can be reached at cwetzstein@washington times.com.