Saturday morning, after returning from a frustrating trip to the G-20 in St. Petersburg, President Obama used his weekly address to try once more to make the case for U.S. action against Syria. Although the Senate Foreign Relations Committee approved a draft resolution authorizing military action (with a 90-day limit and a ban on ground troops), congressional support seems problematic and support from a war-weary public has failed to materialize. Russian President Putin, a backer of Syrian President Bashar al-Assad, of course opposes any strike, but U.S. allies are also reluctant.

The president, who acknowledged Friday that he was elected “to end wars, not start them,” finds himself in a lonely and pressured position.

With a few exceptions like John McCain–who took a beating over his stance at an Arizona town hall–GOP leaders like John Boehner and Eric Cantor, and Democrats like Hillary Clinton and Nancy Pelosi, not many politicians on either the right or the left have expressed backing for American intervention in an already unstable region. It is not clear whether Obama will win the congressional approval he seeks. And he has refused to speculate about whether he would act without that authorization.

Congress returns from recess on Monday and will take up the issue.

In his Saturday address, Obama described the Aug. 21 chemical weapons attack as “not only a direct attack on human dignity; it is a serious threat to our national security. There’s a reason governments representing 98% of the world’s people have agreed to ban the use of chemical weapons. Not only because they cause death and destruction in the most indiscriminate and inhumane way possible–but because they can also fall into the hands of terrorist groups who wish to do us harm.”

“That’s why, last weekend, I announced that, as commander in chief, I decided that the United States should take military action against the Syrian regime. This is not a decision I made lightly. Deciding to use military force is the most solemn decision we can make as a nation.” “As the leader of the world’s oldest constitutional democracy, I also know that our country will be stronger if we act together, and our actions will be more effective. That’s why I asked members of Congress to debate this issue and vote on authorizing the use of force.” “What we’re talking about is not an open-ended intervention. This would not be another Iraq or Afghanistan. There would be no American boots on the ground. Any action we take would be limited, both in time and scope–designed to deter the Syrian government from gassing its own people again and degrade its ability to do so.” “I know that the American people are weary after a decade of war, even as the war in Iraq has ended, and the war in Afghanistan is winding down. That’s why we’re not putting our troops in the middle of somebody else’s war.” “But we are the United States of America. We cannot turn a blind eye to images like the ones we’ve seen out of Syria. Failing to respond to this outrageous attack would increase the risk that chemical weapons could be used again; that they would fall into the hands of terrorists who might use them against us, and it would send a horrible signal to other nations that there would be no consequences for their use of these weapons. All of which would pose a serious threat to our national security.” “That’s why we can’t ignore chemical weapons attacks like this one–even if they happen halfway around the world. And that’s why I call on members of Congress, from both parties, to come together and stand up for the kind of world we want to live in; the kind of world we want to leave our children and future generations.”

President Obama has canceled a planned trip to Los Angeles in order to stay in Washington to speak with lawmakers on Monday and Tuesday, and he has scheduled a speech to the nation on Tuesday.