SOMEDAY, A WOMAN WILL BE President!" To Ann Ruben, a Miami Lakes, Fla., psychologist, it seemed an unexceptionable sentiment, especially coming from Margaret, the bespectacled feminist-in-training from Hank Ketcham's "Dennis the Menace" comic strip. Ruben, 70, who has spent much of the last five years researching children's attitudes about self-esteem, decided Margaret's cry from the heart would make a dandy T-shirt. And so, with Ketcham's permission, she had a batch of shirts printed. So far, so good.

Ruben thought she had it made when her local Wal-Mart in Miramar, Fla., started selling her Ts. Then a customer or two—Wal-Mart officials won't say how many—complained about the "political" message on the shirts, and they were pulled from the shelves. Ruben was aghast. "I was never aware that promoting women as leaders flew in the face of family values," she says. "It didn't make any sense."

A woman's place has been an obsession for Ruben since she was a girl. The daughter of Russian immigrants, she recalls when she was 8 and playing with an older cousin, Irwin Molever. "Annie, you be the secretary," he told her, "and I'll be the president." Ruben happily shuffled papers on Irwin's behalf—for a while. "On Monday, that was fine," she says. "On Tuesday, it was still okay. But on Wednesday, I said, 'It's my turn to be president.' " Irwin scoffed. "Boys are never secretaries," he said, "and girls are never presidents!" Exasperated, Ruben flung her papers at Irwin. "He wasn't pleased," she says. "He punched me in the stomach."

The Wal-Mart rejection came like a punch in the gut as well, only this time Ruben fought back. Last month she took her story to reporters. The result was a storm of complaints—and a promise from Wal-Mart headquarters to buy 30,000 T-shirts, which will soon go on sale nationwide. The victorious Ruben plans to funnel any profits into her Women are Wonderful education foundation—and, like Margaret, she's sure a woman will one day make it all the way in politics. "I'm proud of her," says husband Gershon, 72, a retired insurance agent. "She never lets go, which is how it should be."