The security improvements in most neighborhoods are real. Days now pass without a car bomb, after a high of 44 in the city in February. The number of bodies appearing on Baghdad’s streets has plummeted to about 5 a day, from as many as 35 eight months ago, and suicide bombings across Iraq fell to 16 in October, half the number of last summer and down sharply from a recent peak of 59 in March, the American military says.

As a result, for the first time in nearly two years, people are moving with freedom around much of this city. In more than 50 interviews across Baghdad, it became clear that while there were still no-go zones, more Iraqis now drive between Sunni and Shiite areas for work, shopping or school, a few even after dark. In the most stable neighborhoods of Baghdad, some secular women are also dressing as they wish. Wedding bands are playing in public again, and at a handful of once shuttered liquor stores customers now line up outside in a collective rebuke to religious vigilantes from the Shiite Mahdi Army.

Iraqis are clearly surprised and relieved to see commerce and movement finally increase, five months after an extra 30,000 American troops arrived in the country. But the depth and sustainability of the changes remain open to question.

By one revealing measure of security — whether people who fled their home have returned — the gains are still limited. About 20,000 Iraqis have gone back to their Baghdad homes, a fraction of the more than 4 million who fled nationwide, and the 1.4 million people in Baghdad who are still internally displaced, according to a recent Iraqi Red Crescent Society survey.

Iraqis sound uncertain about the future, but defiantly optimistic. Many Baghdad residents seem to be willing themselves to normalcy, ignoring risks and suppressing fears to reclaim their lives. Pushing past boundaries of sect and neighborhood, they said they were often pleasantly surprised and kept going; in other instances, traumatic memories or a dark look from a stranger were enough to tug them back behind closed doors.