Historian casts a skeptical eye on the emerging Egypt

Wrapped in a shawl on a cold morning, Gamal Banna shuffled over a dusty carpet amid fraying books on old civilizations. He knows well the intricacies of Arab history, but is far less certain where the upheavals of the last year will lead.

Like the balustrade winding to his library door, the known ways are crumbling. Moments of wonder are giving way to months of bewilderment. These days, he said, are likely to prove as seminal as those after World War I, when Western powers drew the borders that shaped the Middle East for nearly a century. Islamists, who have endured decades of oppression, appear to have their chance to redefine the region's politics.

"One era has ended," said Banna, one of Islam's leading liberal thinkers. "But of the new era, we don't know exactly what is taking shape."...