WASHINGTON -- Twelve years later, haunting memories of Sept. 11 are shaping the debate over what to do about Syria.
As Americans mark the anniversary of the 2001 terrorist attacks, the nation again is wrestling with painful questions about al-Qaida, weapons of mass destruction and the risks of American inaction. At the center of the debate is President Barack Obama, who has sought to move the U.S. away from what he has called the "perpetual wartime footing" it found itself on in the years after 9/11.
"America is not the world's policeman," Obama said Tuesday evening as he addressed the nation about the Syria conflict. "Terrible things happen across the globe, and it is beyond our means to right every wrong. But when, with modest effort and risk, we can stop children from being gassed to death and thereby make our own children safer over the long run, I believe we should act."
Some people worry that a U.S. strike in Syria would embroil the American military in an extended and unwinnable conflict in the Middle East, evoking emotions many felt in the years after 9/11 as they watched America's sons and daughters go back for second and third tours in Iraq and Afghanistan.
Others see Syria through a broader Mideast prism involving Iran. They fear that if the U.S. doesn't assert itself now, America will start from a position of weakness if and when it confronts future threats in the region.
When Obama and the first lady stand on the South Lawn of the White House on Wednesday morning to commemorate 9/11 victims with a moment of silence, there's a good chance at least some of these themes will be weighing on the president.
AL-QAIDA AS TOP THREAT
The international terrorist organization headed by Osama bin Laden became synonymous with "America's enemy" in the days after 9/11. More than a decade later, bin Laden is dead and Obama says the group's core is on the path to defeat. But blows to al-Qaida in Afghanistan and Pakistan have come amid growing concerns about al-Qaida's strength in the Arabian Peninsula, North Africa and even Syria.
That foreign jihadi fighters, many linked to al-Qaida, are growing in ranks among rebels fighting Assad's regime is a major concern for lawmakers and the U.S. Assad and his forces have sought to exploit that concern, arguing, in short, that "the enemy of my enemy is my friend."
Assad said of a potential U.S. strike in an interview Sunday with American journalist Charlie Rose, "This is the war that is going to support al-Qaida and the same people that kill Americans in the 11th of September."
STATE OF ALERT
Although Americans are far less jittery about the threat of terrorism than they were in the aftermath of 9/11, they're still keenly aware of turmoil in the Middle East and its challenges for the U.S.
Nearly all Americans -- 94 percent -- say the war on terrorism has not yet been won, according to a new Associated Press poll. Just 14 percent of those Americans say it's likely the U.S. will win it during the next 10 years.
Such sentiments were punctuated Tuesday when Obama, hours before his national address on Syria, signed a notice extending the national emergency for another year.
"The terrorist threat that led to the declaration on Sept. 14, 2001, of a national emergency continues," Obama wrote to Congress.
Compounding concerns have been new threats to America's embassies and consulates. A threat from Al-Qaida in the Arabian Peninsula led to the closing of 19 diplomatic posts across the Mideast and in Africa last month. And as Obama considered a strike in Syria last week, the State Department was ordering nonessential American diplomats to leave the U.S. Embassy in neighboring Lebanon because of the potential for retaliation from Iran-backed Hezbollah, a group allied with Assad.
IRAQ AND AFGHANISTAN
With the U.S. military struggling to absorb deep automatic spending cuts, few Americans are eager for the U.S. to get involved in a civil war already raging for more than two years, with no end in sight.
Obama, who ran for president as a critic of the Iraq war, ended it as president and is winding down the U.S. war in Afghanistan, is of similar mind.
"I know how tired the American people are of war generally, and particularly war in the Middle East. And so I don't take these decisions lightly," Obama said in an NBC interview Monday.
Obama and his aides know many Americans reflexively resist anything that calls to mind the aggressive stance President George W. Bush took after 9/11. They're insisting any U.S. action will be limited and won't involve troops on the ground.
"This is not Iraq or Afghanistan," Obama's chief of staff, Denis McDonough, said repeatedly Sunday on political talk shows.
But Republicans are hearing a slightly different message. House Majority Leader Eric Cantor, R-Va., arranged for Republican congressional staffers to hear from Stephen Hadley, Bush's former national security adviser, and Eric Edelman, once a top aide to Vice President Dick Cheney. Both played major roles in the Iraq war and are now selling leery Republicans on a strike in Syria.
WEAPONS OF MASS DESTRUCTION
"The lesson of September the 11th is take threats before they fully materialize," Bush said in August 2006.
Those days, it was erroneous intelligence claiming Saddam Hussein had weapons of mass destruction that incensed many Americans as civilian deaths hit record highs three years into the war in Iraq.
Today, there are few doubts chemical weapons have been used in Syria. Assad's regime even acknowledged publicly this week that it possesses the weapons when it agreed to give them up as part of a budding diplomatic deal to avert a U.S. strike.
Obama acknowledges that Syria poses no direct or imminent threat to the U.S. But his pitch to Congress, the public and U.S. allies is rooted in the belief that if the world doesn't act now to uphold a global norm against chemical weapons use, we all could be at risk down the line.
"Sometimes wars have started later because people didn't do things that might have prevented them earlier," Secretary of State John Kerry said Tuesday.