Hey Obama, yes we can. Troops out of Afghanistan, chanted the crowd. Barack, Barack, Barack, Afghanistan's the same as Iraq. And this: NoBomba! At last weekend's anti-war protest in Washington -- the first of the Obama era -- the refrains were clever, if perhaps somewhat predictable. But the frustration of the activists was hardly canned.

"It doesn't look like Obama is changing anything," said Kyle Quigley, an Iraq War veteran who had traveled from Harrisburg, Pennsylvania, to attend the rally. The president's decision to delay withdrawal from Iraq by three months is a sign, Quigley argued, of Obama's "backsliding" on his campaign promise to end the war. Quigley's frustration with the president was shared by many of the anti-war activists at the rally, which was sponsored by the group Act Now To Stop War and End Racism.

Cautious and pragmatic, Obama has always been more centrist than his supporters on the left. His 2008 pledge to raise troop levels in Afghanistan and his vow to be as "careful getting out" of Iraq "as we were careless going in" disappointed those looking for a swift rejection of George W. Bush's foreign policy. Now two months into his presidency, Obama's cautious centrism has provoked an inevitable rift with some of the most devoted interest groups that swept him to power.

But the anti-war grassroots is having a hard time turning their frustration into a movement. Saturday's march underscored the difficulty of implementing an effective protest strategy at a time when the president's approval rating is hovering around 60 percent and the country remains focused on its economic struggles at home. Organizers estimated Saturday's crowd to be 10,000, but Arlington County police said the crowd was between 2,500 and 3,000. From what I could observe, the turnout seemed much closer to the latter figure.

Many activists at the event were disappointed by the turnout. "How can we ensure that our next demonstration is larger than this one?" pleaded Jerry Young of The National Assembly to End the Iraq and Afghanistan Wars, yelling into a megaphone across from the Lincoln Memorial. Some protesters conceded that complacency has set in among anti-war activists who supported Obama during the election. "Most people are really hopeful that things might change with the new administration," admitted Joelle Jameson, who attended the march with an Amnesty International chapter based in Norfolk, Virginia. For many organizers, "Obama is still in his honeymoon period", she said. And the bad economy, said Greg Coleridge of the American Friends Service Committee, "is interrupting the movement and taking up people's time and energy."

The anti-war grassroots also seem to be having a hard time developing a coherent and focused message. Though withdrawal from Iraq and Afghanistan was ostensibly the theme of the day, Saturday's featured speakers railed against causes as disparate as the embargo of Cuba, U.S. policy towards Sudan, and Israel's recent incursion into Gaza. As protesters made their way from the National Mall toward the Pentagon and a hub of defense contractors in Arlington, the march devolved into a vague condemnation of "the military industrial complex" rather than a targeted attack on the president's foreign policy.

Like the blood-stained Israeli flags and "9/11 Was An Inside Job" placards that cropped up along the march, this inability to strike a unified theme demonstrated the movement's continued obstacles to achieving broad-based popular support. After participating in the 1967 March on the Pentagon, Norman Mailer declared the protests a success because "a sense of danger had finally come ... to the damnably mediocre middle of the Left." As Saturday's march traced the same iconic route between Highway 395 and the Potomac River, it seemed unlikely that the student groups, Muslim-American delegations, and veterans in attendance would instill the country's mediocre middle with a comparable sense of urgency.

But organizers are hopeful the tide will eventually turn against Obama's go-slow approach. A Gallup poll released this month shows opposition to the war in Afghanistan at an all-time high, with 42 percent of Americans now saying the United States made a mistake sending troops to the country. If the economic crisis continues to intensify, more and more Americans could come to believe that the country no longer possesses the fiscal and military resources to sustain long-term nation-building overseas. As President Obama takes ownership of American foreign policy, some Republicans might even warm to this position, returning to the isolationist posture many in the party adopted during the 1990s.

Near the end of the march, as the crowd snaked away from Lockheed Martin headquarters in the early evening light, I watched a member of the rally's "young anarchist" contingent speed by me with a large hammer, smashing a window before disappearing into a crowd of his black-clad peers. It was an aberration, a rare moment of violence punctuating an otherwise peaceful day of protest, but it was hard not to see the broken glass as a symbol of the marchers' misplaced energy. Not realizing, or simply not caring, that we had moved past the Lockheed Martin complex, he had smashed the lobby window of the apartment building next door.

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