Obama, who has called Syria’s use of chemical weapons in its
"What's happening in Syria is a blemish on the international community generally," he said. Confirmed use of poison gas by Syrian forces would be "a game changer not simply for the United States, but for the international community."
Obama was asked directly if that meant his administration would take military action.
"By 'game changer,' I mean that we would have to rethink the range of options that are available to us," he said. If the White House obtains conclusive proof of poison gas use, "that means that there's some options that we might not otherwise exercise that we would ... strongly consider."
Obama first warned Syrian President
But since the White House last week announced that U.S. intelligence agencies had concluded with varying degrees of confidence that sarin, a nerve agent, had been released in Syria, Obama has made it gradually clearer that he is far from embracing a military option that might pull the United States into another war.
Obama emphasized Tuesday that while evidence indicates some use of chemical agents occurred, investigators have yet to determine if regime forces intentionally used poison gas, if it was accidentally released or if insurgents or other groups fired the weapons.
He said conclusive proof was necessary to win international support for action.
"If we end up rushing to judgment without hard, effective evidence, then we may find ourselves in the position where we can't mobilize the international community to support what we do," he said. "There may be objections even among some people in the region who are sympathetic with the opposition if we take action. So ... it's important to do this in a prudent way."
Some members of
But White House and senior
Conservative lawmakers and their allies say Obama has raised the bar so high that it is unlikely he will take action. They argue that Iran and North Korea will view his response as a signal that U.S. threats can be ignored.