WASHINGTON (USA TODAY) -- In a series of stunning defeats for Iraqi government forces, radical militants moved closer toward Baghdad on Wednesday, seizing key cities and confronting President Obama with a fresh foreign-policy crisis.
The Pentagon said battling the militants is the responsibility of the Iraqi security forces, reflecting the administration's determination to keep ground troops out of Iraq, which they had helped stabilize after more than eight years of war.
For now, Obama has few choices. State Department spokeswoman Jen Psaki said the U.S. likely will give Iraq new assistance to combat insurgents. The U.S. is considering whether to conduct drone missions for Iraqi forces, the Associated Press reported, citing an unnamed senior Pentagon official.
The U.S. already has expedited weapons sales to Iraq this year, including missiles, ammunition, and other equipment and arms.
The fall of Baghdad — or outbreak of a civil war — would raise the stakes considerably. It would further traumatize the tumultuous region and raise questions about whether the U.S. squandered the progress it made there.
White House spokesman Josh Earnest said, "We've been in touch with the government of Iraq about what we can do to support them."
But Pentagon spokesman Col. Steve Warren stressed it is up to Iraqi armed forces "to step up to fight and defeat this enemy."
Officials have not said what happens if the Iraqi forces can't.
The militants have "seized really strategic terrain with huge swaths of population," said James Jeffrey, a former U.S. ambassador to Iraq. If they threaten Baghdad, the U.S. may have to use air power to support Iraqi security forces, Jeffrey said. "If we don't support them from the air, these guys are going to crumble," he warned.
Iraqi forces are battling the Islamic State of Iraq and the Levant, a breakaway al-Qaeda group that earlier this year seized key cities west of Baghdad. The group operates in Syria and Iraq.
On Tuesday, insurgents overran parts of Mosul, Iraq's second-largest city, and on Wednesday attacked Tikrit, hometown of former dictator Saddam Hussein and 80 miles north of Baghdad.
Some news reports said that militants also seized portions of Baiji, a key oil refining town. They have nearly circled Baghdad, Jeffrey said. "If those areas cannot be held, Baghdad can be strangled." He said they've captured weapons and infrastructure.
The worsening situation is likely to renew a debate at home over the wisdom of starting the war, in which more than 4,000 U.S. troops died, and withdrawing combat forces in 2011.
Iraq was relatively stable at the time, but a continued U.S. military presence would have helped lock in those gains, some officers say. "We prematurely walked away," said Jim Lechner, a retired Army lieutenant colonel with extensive experience in the region.
Morale in the Iraqi army has plummeted, analysts say. "There is no desire to fight," said Waleed Alrawi, a retired Iraqi brigadier general now living in Florida.
Contributing: Tom Vanden Brook and David Jackson