During a recent family vacation to the Grand Canyon, Michelle Obama stepped off Air Force One in a pair of “short shorts” that some are calling inappropriate.

The midthigh jeans shorts Obama sported are something most American women would wear without a second thought. But were they a fashion faux pas for a first lady?

“I think the question is, what could be more appropriate than shorts for hiking the Grand Canyon with your family in mid-August?” said Mary Tomer, who founded Mrs-O.org, a Web site that monitors Obama’s style, on the TODAY show Wednesday.

Any first lady’s fashion choices are closely watched, but interest in Obama’s style has bordered almost on obsession. When Obama showed her spectacularly toned arms in a sleeveless gown at the Inaugural Ball, it sparked such a media maelstrom, you’d think she’d shown up in the nude.