Still grappling with the brutal video killing of an American journalist this week, Pentagon leaders defended a failed rescue effort from earlier this summer and refused to publicly rule out the chance of attacks against Sunni militants in their home bases in Syria.

"I don't know any other way to describe it, other than barbaric," said Secretary of Defense Chuck Hagel at a Pentagon news conference, as he denounced the execution of journalist James Foley and said the United States would not back off because of threats to kill other Americans.

"I think the President has been very clear on this," Hagel added. "We continue to explore all actions regarding ISIL."

Asked specifically if that air strikes inside Syria, Hagel wouldn't say yes, but he didn't say no, either.

"We're looking at all options," the Secretary said.

As for the failed mission in Syria to rescue Foley and other Americans being held by Islamic militants, Hagel joined the Chairman of the Joint Chiefs of Staff in praising the work of U.S. commandos.

"The mission was executed flawlessly," said Gen. Martin Dempsey of the effort to get U.S. special forces inside Syria. "It turned out the hostages were no longer at that location."

While Hagel and Dempsey both said the threat from ISIL forces was clear to the U.S., neither man laid out any more aggressive plan, drawing the ire of Republicans.

"We need to step up our game on taking out weaponry equipment as well as ISIL personnel," said Sen. Saxby Chambliss (R-GA) on CNN. "We know who they leaders are and where the leaders are."