U.S. President Barack Obama says he resisted military action in Syria during the first two years of the conflict because "we cannot solve someone else's civil war through force."
In a speech to the nation Tuesday night, President Obama cited the cases of Iraq and Afghanistan as examples to support that notion.
But he said the situation changed after August 21 when Syrian President Bashar al-Assad's forces gassed to death hundreds of people, including children.
On what he called "that terrible night," Mr. Obama said the world saw in gruesome detail why an overwhelming majority of people have declared chemical weapons off limits. He said the images of the attack are "sickening."