WASHINGTON — When President Barack Obama concluded his inaugural address, Joe Halloran grinned at his wife, Barbara Henry, and let out a sigh of awe. Through the speech, the two had glanced at each other excitedly, fidgeting whenever Obama struck an especially forceful tone. At a certain point, Joe sat down on the grass and closed his eyes.

Joe and Barbara had never attended an inauguration before Obama was first sworn in in 2009, an occasion Joe described as “marvelous.” Still, he said, the president’s second swearing-in was even more meaningful.

“The first time, it could have been a fluke,” he said. “He was elected, he did a good job, he was elected again. It makes it real clear the country is moving in a different direction.”

For Obama supporters like Joe and Barbara, Obama’s second inaugural address was a welcome change from the speech he gave in 2009. Rather than striking a tone of hope and change, Obama adopted a more aggressive air, not unlike the slogan he used throughout his campaign: “Forward.” His combative rhetoric stood in stark contrast to the tone of bipartisanship he presented four years ago, instead jabbing at political rivals for holding back his agenda.

But not everybody who attended the inauguration shared Joe and Barbara’s enthusiasm. Francis, a substance abuse counselor from Atlanta, Ga., who declined to give his last name, was loudly advertising black scarves on which he had embroidered inauguration-themed slogans. Francis said he attended Obama’s first inauguration four years ago.

“For the first time, a black man was chosen by the people, not by one person but by all the people, and that made it amazing for me,” he said.

This time, though, Francis considered his time better spent selling scarves.

Four years in office have chipped away at Obama’s approval rating, with an acrimonious health care fight, the emergence of the Tea Party and a prolonged conflict over the debt ceiling bringing his approval rating to a low of 44 percent in 2011. On Monday, Gallup reported a 50 percent approval rating, down from his 69 percent approval rating just three days after his first swearing-in.

This decline in excitement could be seen in the size of Monday’s celebration. While most sources placed attendance at Obama’s first inauguration at approximately 1.8 million people, pre-inauguration Capitol security officials projected that approximately 600,000 would attend Monday’s celebration. In 2009, attendees struggled to find a spot on the National Mall as far back as the Washington Monument; this year, the crowd was noticeably thinner.

Charles Suey, a merchandise vendor, attended both inaugurations to sell Obama buttons with a variety of slogans like “evolved” – a reference to the president’s self-described thinking on gay marriage. Suey said that, in 2009, he created 14,000 buttons to sell; this year, he made just 3,000.

George Gonsalves, a C-SPAN intern who was handing out Obama buttons for free elsewhere on the mall, said that, despite the decreased turnout this year, excitement was still palpable for those in attendance. In fact, the smaller crowd may have been a benefit.

“Last inauguration, some of that excitement translated to a lot of kicking, a lot of arguing, a lot of pushing,” he said. “People just started fighting — normal people were trampling each other.”

Gonsalves added that he lost some of the enthusiasm he had felt for Obama in the four years between inaugurations. He criticized Obama for what he deemed a lack of difficult decision-making.

“Obama really has to show a stronger face,” he said.

Joe and Barbara conceded that “decisive action” would be a tough feat for the president, who is entering his second term with a divided Congress. Already, several tough fights loom on the horizon, including another renegotiation of the debt ceiling and a plan to strengthen gun laws following the mass shooting in Newtown, Conn.

Still, the couple said they are hopeful.

“It’s not gonna be easy, but I think the country’s moving,” Joe said.