Sens. McCain, Corker and Burr are ready to push back on Obama's agenda.
The Pentagon reversed its decision to wait until Congress approved funding.
Lawmakers are wading deeper into the defense issues they left on the backburner.
He said he would not send forces "into harm’s way with their arms tied behind their backs."
"This gradualism, unfortunately, is beginning to remind me of the Vietnam War," he said.
The administration wanted to secure action from Congress first, said the Pentagon.
The new deployment brings the total number of U.S. troops to 3,200.
Senate Republicans to push for change on Iran, Ukraine and ISIS.
Troops are scheduled to leave in 2016. Do they need to stay longer?
"There's always going to be some margin of error," said officals about airdrops.
Turkish government has been "part of the problem," says Florida lawmaker.
Kerry tried to reassure Turkey, which has concerns about arming Kurdish groups.
McCain earlier this year said Obama's handling of Syria made him worse than Carter.
The secretary of State said U.S. strategy against ISIS is "starting to gain traction."
The Defense secretary said the group's gains had been "reversed" in some areas.
Senators said an ISIS measure shouldn't limit military options.
VA Secretary McDonald touted the "largest reorganization" in agency history.
Obama said an increase in coalition partners could lead to a decrease in U.S. troops.
The House Intel Chairman warned of concerns among Sunni Arab nations.
The former lawmaker warned of "expanded neocon wars" under a GOP Senate.
The secretary will "express America's solidarity with the Canadian people," an official said.
The bombing campaign has averaged $7.6 million per day since August.
The U.S. launched a new wave of strikes and dropped arms for the Kurdish town.
When it comes to foreign policy, we always seem to be fighting the last war.