"For several years now what we've been seeing is a slowly unfolding disaster for the Syrian people," Obama said in a wide-ranging impromptu news conference in the White House briefing room.
The president said the United States has worked to strengthen the opposition and worked with allies to help Syrian President Bashar Assad to be forced out of office.
Obama said use of chemical weapons is a "game changer" for not just the United States but the international community as a whole. But, he said, though there's evidence chemical weapons were used, there remain questions about who was responsible.
He said he will not "rush to judgment."
"I've got to make sure I've got the facts ... hard effective evidence," he said. "We are already invested in the trying to bring about a solution to the violence in Syria. I won't go into detail about what those options might be."
Asked about the Boston Marathon bombings and last year's attack on the U.S. Consulate in Benghazi, Libya, Obama said Sen. Lindsey Graham, R-S.C., is wrong in saying the United States has gone backward on national security.
"No, Mr. Graham was not right on the Boston attack and Benghazi," he said.
Graham has charged the Boston Marathon bombing and the attack on the U.S. Consulate in Benghazi, Libya, are examples of a failure in U.S. intelligence gathering. Obama said the attacks were not intelligence failures, that both incidents are being fully investigated and every step taken beforehand will be reviewed.
"Based on what I've seen so far, the FBI performed its duties, the Department of Homeland Security did what it's supposed to be doing. ... Because of the pressure we have put on al-Qaida ... one of the dangers we now face are self-radicalized individuals ... who may not be part of any network [who decide to attack]. ... Those are in some ways more difficult to prevent," Obama said.
In a question on Washington politics, Obama decried the 60-vote rule to end filibusters in the U.S. Senate, saying it's "gumming up" the works. The president said he's confident he'll be able to get his agenda through Congress because of the growing sense that "we have to get past" the dysfunction in the federal government.
He said the first order of business is to end the $85 billion sequester that cuts federal spending across the board.
Obama said it's not his job to get members of Congress to "behave." It's their job, he said, to do the right thing for the American people.
He called on Congress to help him come up with a broader budget deal.
Asked about hunger strikes by detainees at the detention facility in Guantanamo Bay, Cuba, Obama said Guantanamo "is not necessary to keep America safe" and actually hurts anti-terror efforts.
"Congress determined they would not let us close it," Obama said, calling it a "no-man's land," saying it's "contrary to who we are."
He called on Americans to reflect on why we're keeping the facility open when other terrorists have successfully been tried in civilian U.S. courts and are being held in federal prisons.
"We can handle this," he said.
Obama defended is healthcare reforms saying Obamacare had made medical insurance more secure for people who already have health coverage.
"The challenge is setting up ... an online marketplace ... that's still a big complicated piece of business," he said.
The president also said he looks forward to traveling to Mexico to discuss border security and other issues with President Enrique Pena Nieto.
"We've made great strides in cooperation and coordination with Mexico over the last few years," he said.
Obama said he had a chance to talk to NBA player Jason Collins, the first openly gay player in a major U.S. sport league, Monday and that he told him, "I couldn't be prouder of him." I think it's a great thing."
Collins, a 34-year-old free agent center for the Washington Wizards came out in an article on the Sports Illustrated website.