The Syrian government has said it didn't use chemical weapons in the August 21 attack. It says jihadists fighting alongside Syrian rebels used them to turn global sentiment against the regime. Syria's prime minister says the country's army is on "maximum readiness and fingers are on the trigger to confront all challenges."
What about the Syrian opposition?
A major Syrian opposition group, the Syrian National Coalition, said it was disappointed by Obama wanting Congress' permission. "We can't understand how you can promise to help those who are being slaughtered every day in the hundreds, giving them false hope, then change your mind and say 'Let's wait and see,'" the group told CNN.
And the Local Coordination Committees in Syria, another opposition group, lamented the notion that a U.S. strike would be limited.
"A limited strike to merely warn Assad today will lead to nothing but his increase in violence, as well as to his complete confidence that no one would prevent him from killing," the group said in a statement. "In the end, no one will pay the price but the Syrian people."
How exactly would U.S. carry out an attack?
No one is calling for boots on the ground. Five U.S. warships with Tomahawk cruise missiles are waiting in the Mediterranean Sea. The Tomahawk has a range of about 1,000 miles. It can loiter over targets, circling for hours, and can be reprogrammed midflight to change course. Yes, each costs about $1.2 million, but they can be fired from quite a distance. This means no one has to get within range of Syrian fire.
Could Syria strike back?
Syria has some anti-ship missiles -- but they have a range of only 62 to 186 miles, says Edward Hunt, a senior analyst at IHS Jane's. It also has a number of Scuds and similar surface-to-surface weapons, but these are not designed to be used against moving targets such as U.S. warships, Hunt said.
How are the neighbors reacting?
Security is tight in Lebanon, where one in six is now a Syrian refugee. In Israel, there's been a rush on gas masks because residents fear that Syria could target Israel for retaliation. And Jordan, a key Western ally, says it won't be a launchpad for a strike.
This is all a lot to digest. Give me the takeaway.
A U.S. strike against Syria is not imminent. And even though Obama can launch a military attack unilaterally, he'd prefer to have Congress' approval first.