For months the American flag has been showing up on cars, porches, football helmets and basketball uniforms. The display has made us wonder about the meaning of this unprecedented—for this generation—expression of patriotism. It is, of course, a display of solidarity with the victims of the terrorist attacks and with the firefighters and police officers who tried to rescue them. But why has the flag, the symbol of the nation, been the vehicle for this expression and not, say, a yellow ribbon? What notions of American purpose and identity have been evoked? Does the flag-waving signal a renewed commitment to national ideals and to a sense of common destiny? Might it indicate a new willingness to sacrifice for the sake of the larger community? Or is it simply a way of encouraging the military pursuit of Osama bin Laden and the al-Qaeda network?

Whatever the sentiments behind the flag-waving, sociologist Robert Putnam has detected a new civic mood in the nation since September 11. Putnam, who has previously lamented the collapse of community life and who coined the term “bowling alone” to describe Americans’ individualistic isolation, reports in the American Prospect that people’s trust in national and local governments has increased significantly. His polling data from late 2001 also indicate that Americans are more confident that their neighbors will cooperate in a time of crisis. And they express more interest in politics. Putnam concludes that the terrorist attacks have made Americans “more united, readier for collective sacrifice and more attuned to public purpose” than they have been for decades.

Not all the news is encouraging, however. The new mood has been expressed “largely through images,” not actions. Attitudes have changed more than behaviors. People are not rushing out to join civic organizations or church groups.

Nevertheless, Putnam thinks, this is a moment to be seized—a time for institutions and government to tap into people’s readiness for action, even sacrifice, on behalf of a common cause. He recommends an expansion of Americorps, the domestic Peace Corps program which puts young people to work building homes or tutoring students in low-income communities. Senators John McCain and Evan Bayh want to expand that program from 50,000 to 250,000 participants by 2010.

Charles Moskos thinks the war against terrorism furnishes the occasion for an even larger expression of public purpose—the revival of the draft. Moskos, a Northwestern University sociologist who studies the military, has for years argued that the return of an equitable draft that would enlist young people ages 18 to 25 in military or nonmilitary service would enrich civic life by providing a range of help to the nation—whether in airport security, border patrols, environmental cleanup, health or education—and by giving young people a common experience of service. A draft that applied to all regardless of wealth or education (something the U.S. hasn’t experienced since the 1950s), says Moskos, would be a democratizing experience and would instill in young people a sense of being part of a larger community.

The revival of an equitable draft is not on anybody’s political front burner. Even the creative expansion of volunteer programs faces political hurdles. But it’s attention to these kinds of efforts that would indicate a serious public purpose behind the flag-waving.