Obama has made no final decisions and could ultimately approve limited strikes if stronger targets emerge, the officials say. The CIA and other spy agencies are scrambling to close intelligence gaps in the region and track the movements of key figures in the militant group known as the Islamic State in Iraq and the Levant, which seized Mosul, Tikrit and other towns in Iraq as parts of the country's military melted away.
The president summoned top congressional leaders to the White House Wednesday afternoon to discuss the collapsing security situation. The relentless violence marks the greatest threat to Iraq's stability since the U.S. military withdrew at the end of 2011 after more than eight years of war.
Ahead of his meeting at the White House, Senate Majority Leader Harry Reid said the U.S. had no business sending troops into the midst of what he called Iraq's civil war.
"It's time for the Iraqis to resolve it themselves," said Reid, a Nevada Democrat. Taking on Republicans who have blamed the current violence on the withdrawal of U.S. forces, Reid said, "Those who attack President Obama for bringing our troops home from Iraq are wrong and out of step with the American people. After a decade of war, the American people have had enough."
Obama has ruled out returning combat troops to Iraq in order to quell the insurgency. However, he has notified Congress that up to 275 armed U.S. forces are being positioned in and around Iraq to provide support and security for U.S. interests.
Obama is also considering sending a small contingent of special operations forces to help train the Iraqi military, officials have said. Other options under consideration include boosting Iraq's intelligence about the militants and, more broadly, encouraging the Shiite-dominated government in Baghdad to become more inclusive.
The U.S. has also made initial overtures to its long-time foe Iran, which has an interest in seeing the Iraqi government survive, though officials have ruled out the possibility of military cooperation with Tehran.
House Speaker John Boehner, R-Ohio, said Wednesday that he opposed outreach to Iran on grounds that it would send the wrong message to American allies in the Middle East given that the Islamic republic is alleged to have sponsored terrorism in the region. Boehner is among the leaders meeting with Obama at the White House.
The most aggressive option under consideration at the White House has been airstrikes, most likely by drones, though officials have also looked at the possibility of launching strikes from manned aircraft. However, at this point, officials have been unable to identify clear targets the U.S. could hit in Iraq that could slow the militants' momentum.
Gen. Martin Dempsey, the chairman of the Joint Chiefs of Staff, said Wednesday that the U.S. does have a request from the Iraqi government for the Obama administration to use air power to stop the militants.
So far it's unclear whether the CIA and the NSA have been able to locate the top insurgent figures, such as Abu Bakr al-Baghdadi, the ISIL's leader. Al-Baghdadi, who was released in 2009 after spending four years in U.S. military custody in southern Iraq, came away with an appreciation of American monitoring technology that made him an elusive target once he took command, said Richard Zahner, a retired Army general and former senior NSA official.
Intelligence agencies have been tracking the ISIL for years, officials say, watching closely as it grew stronger in the Syrian civil war and began to challenge the Shiite-dominated Baghdad government.
The CIA and other agencies are assembling detailed dossiers known as "targeting packages" that amount to profiles of insurgent commanders, including as much day-to-day information as can be gathered about their location, movements, associates and communications. Those packages can be used to target subjects for drone strikes or other military action, though they also can be used for nonlethal purposes, current and former officials say.
The officials would not be quoted by name because they were not authorized to discuss the classified details publicly.
The U.S. already has a range of ground, air and sea troops and other assets in the region. They include six warships in the Persian Gulf, including the aircraft carrier USS George H.W. Bush and the amphibious transport ship USS Mesa Verde, which is carrying about 550 Marines and five V-22 Osprey hybrid aircraft.
There are about 5,000 U.S. soldiers across the border in Kuwait as part of a routine rotational presence, several Air Force aircraft capable of a full range of missions and intelligence gathering and surveillance assets, including drones, in the region.
Associated Press writers Bradley Klapper, Alan Fram, Donna Cassata and Lolita C. Baldor contributed to this report.
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