President Barack Obama opened the door to a diplomatic way out of the crisis in Syria -- while refusing to close the door on military intervention -- in a nationally televised speech Tuesday night.
Here are key developments from Capitol Hill, the White House and across Washington before, during and after the president's address.
10:44 p.m. ET - House Intelligence Committee Chairman Mike Rogers in a statement said he's "hopeful a diplomatic solution can be reached, however, I am skeptical of any proposal proffered by the Russians and doubt Assad's motives for agreeing to this plan ... the President still urgently needs to develop and execute a coherent strategy to address all of those threats."
10:34 p.m. ET - 6 in 10 Americans who watched the president's speech tonight said they favor his approach, according to CNN's instant poll taken after Obama spoke. Sixty-one percent said they support the president's position in Syria and 37% said they oppose his response.
The poll indicated that nearly two-thirds of those who watched the speech think the situation in Syria is likely to be resolved through diplomatic efforts, with 35% disagreeing. Speech-watchers were divided on whether Obama made a convincing case in his speech for U.S. military action in Syria, with 47% saying he did and 50% saying no.
10:26 p.m. ET - National Security Advisor Susan Rice tweets: "POTUS: when dictators commit atrocities, they depend upon the world to look the other way until those horrifying pictures fade from memory."
10:18 p.m. ET - CNN's John King tweets: "post #syria speech POTUS still faces #GOP #congress doubts: @ChuckGrassley says leaning no; @SenOrrinHatch still "strong reservations."
10:11 p.m. ET - CNN's Dan Merica tweets: "Another undecided D break Syria silence. MT @RepRickLarsen President takes diplomatic opening, Syria must match its words with deeds."
10:03 p.m. ET - Republican Senators Lindsey Graham and John McCain issued a joint statement saying, "We appreciate the President speaking directly to the American people about the conflict in Syria. We regret, however, that he did not speak more forcefully about the need to increase our military assistance to moderate opposition forces in Syria, such as the Free Syrian Army. We also regret that he did not lay out a clearer plan to test the seriousness of the Russian and Syrian proposal to transfer the Assad regime's chemical weapons to international custody."
10:01 p.m. ET - Reacting to the speech, Republican Sen. Charles Grassley, who met with Vice President Joe Biden yesterday and with the president today on Capitol Hill said, "I don't think the case for military action has been made ... I'm still leaning against the authorization for the use of force that's been presented.
10 p.m. ET - CNN's Dan Merica tweets: "@ChrisMurphyCT, a Democratic senator who was against strikes from the beginning, tweets "Good speech. President right to delay vote."
9:59 p.m. ET - Sen. Lindsey Graham, R-South Carolina, tweets: "After this impassioned plea I cannot imagine Pres Obama not launching military strike if diplomacy fails, regardless of what Congress does.
"You cannot make moral case as the leader of the Free World and then refuse to act if diplomacy fails. #SyriaSpeech."
9:58 p.m. ET - Democratic Sen. Levin, chairman of the Senate Armed Services Committee, in a statement said "I believe Congress can best support the goal of a diplomatic solution by approving a resolution that authorizes the use of force if Syria refuses to give up its chemical weapons."
9:54 p.m. ET - Republican Sen. Rand Paul on CNN said he hopes the Russia/diplomatic option works because if we attack, Syria will be more unstable. Paul said the chance al Qaeda gains traction in the region increases if the United States attacks.
9:45 p.m. ET - The Progressive Change Campaign Committee, a left-leaning advocacy group that has been opposed to military action in Syria, responded to the address saying "public pressure worked."
"The American people knew that diplomacy was a credible and strategic option, and this great news from President Obama will be better for America and his presidency than dropping bombs on Syria," the group said in a statement.
9:43 p.m. ET - Republicans National Committee Chairman Reince Priebus responded to the president's address by saying, "The administration's handling of the U.S. response to Syria has been so haphazard it's disappointed even the president's most ardent supporters."
"This rudderless diplomacy has embarrassed America on the world stage. For a president who campaigned on building American credibility abroad, the lack of leadership coming from the Oval Office is astounding," Priebus added.
9:42 p.m. ET - House Minority Leader Nancy Pelosi, D-California, tweets: "Pres. Obama's leadership brought diplomatic solutions back to the table, shows his willingness to exhaust every remedy before use of force."
9:40 p.m. ET - CNN contributor Donna Brazile tweets: "POTUS must keep the threat of military action on the table until #Syria gives up its chemical weapons and an int'l team can verify. #peace."
9:31 p.m. ET - CNN Senior Political Analyst David Gergen tweets: "Very good Presidential speech -- crisp, clear, addressed doubts. Not sure enuf to to persuade anywhere close to majority. @AC360."
9:30 p.m. ET - Ari Fleischer, a spokesman for then-President George W. Bush and now a CNN contributor, tweets: "Assad denies using CW that O deplores. Putin sides w Assad. So O turns to Putin & Assad 2 get rid of weapons that weren't used."
9:28 p.m. ET - CNN's Jake Tapper tweets: "A speech to a public that doesn't want to go to war by a president who doesn't want to go to war."
9:24 p.m. ET - Democratic Rep. Elijah Cummings of Maryland, who is still undecided on a military strike, said the president made a "great moral argument," especially when he said U.S. troops could be gassed. But he still has to make it clear that this will not "mushroom into something else."
9:19 p.m. ET - CNN's Jessica Yellin tweets: "American exceptionalism: @BarackObama often accused of apologizing for America, makes case for using America's mil might to defend values."
9:17 p.m. ET - White House Deputy Press Secretary Eric Schultz tweets: "President Obama: "The burdens of leadership are often heavy, but the world is a better place because we have borne them."
9:15 p.m. ET - Obama asks what kind of world we would live in if we watch a leader violate international law with poison gas and "look the other way."
9:14 p.m. ET - CNN's Jim Acosta tweets: "Obama confirms he's asked Congress to "postpone" a vote while Russia proposal takes its course."
9:13 p.m. ET - Obama said it's too early to tell if the latest diplomatic efforts will succeed, but there is now the possibility that Syria will be rid of chemical weapons "without force." As part of those efforts, he said he asked Congress to put off any votes on action and will send Kerry to meet with Lavrov this week.
9:12 p.m. ET - Obama said he agrees the US should not be the world's policeman and said he has a "deeply held preference for peaceful solutions." But the United States "does not do pinpriks."
9:08 p.m. ET - The White House tweets: "Obama: "I have spent 4.5 years trying to end wars---not start them. Our troops are out of Iraq. Our troops are coming home from Afghanistan."
9:09 p.m. ET - Addressing criticism of a potential strike, including one veteran that wrote to the president saying "this nation is sick and tired of war," Obama said he will "not put American boots on the ground," "not pursue an open ended action" and "not pursue a prolonged air campaign." Instead, it would be a "targeted strike."
9:07 p.m. ET - Obama said he determined the US should respond militarily to Assad to deter future action, degrade his ability and make clear the US will not tolerate their use. "That's my judgment as commander of chief," he said. But as president of the world's oldest constitutional democracy, he also felt it was right to bring the decision to Congress.
9:05 p.m. ET - Obama outlined the evidence that led to the conclusion that Assad used chemical. "These things happened. The facts cannot be denied." Now he said, the question is what the US and the international community is "prepared to do about it."
9:02 p.m. ET - Obama said he resisted calls for military action in Syria "because we cannot solve someone else's civil war through force." But the situation "profoundly changed on August 21st." He said the images were "sickening."
9:01 p.m. ET - Obama, standing in the East Room, says he will talk about Syria tonight "why it matters and where we go from here." over the past 2 years.
8:05 p.m. ET - @JohnKingCNN reports the president will not lay out a timetable for diplomacy or potential military action in his address tonight, according to a senior administration official involved in the speech process. The administration believes it can't make those calculations until the Kerry-Lavrov meeting Thursday, the initial eye-to-eye test of whether Russia and the Syrians are serious. Any discussion of when to schedule votes, this official said, should wait until the Kerry-Lavrov meeting, "which will give us a sense of what those alternative resolutions should look like."
The president, in his meeting with lawmakers today, said they should not do anything to take the credible military threat off the table.
7:45 p.m. ET - Former Secretary of State Hillary Clinton, speaking at the National Constitution Center Tuesday night, said Assad's use of chemical weapons violates a universal norm at the heart of our global order that requires a "response from the international community led by the U.S."