White House defends President Barack Obama's plan to fight Islamic State militants

A top White House aide on Sunday defended President Barack Obama's plan to fight Islamic State militants, as the administration sought to persuade the US Congress to back an escalation of the effort.

The Obama administration has been making the case to Congress for wider operations against the Sunni militants, including US air strikes in Syria for the first time, more strikes in Iraq and more military advisers in Iraq.

US lawmakers have generally been supportive of the effort but Republicans, who control the House of Representatives, have accused Obama of not doing enough to deal with the problem sooner and have questioned whether the strategy goes far enough.

In a round of television interviews on Sunday, White House chief of staff Denis McDonough touted the administration's efforts to put together a coalition of Western allies and Gulf Arab states.

"We believe that we have the right strategy that the president laid out for the country on Wednesday night to make sure that we degrade and ultimately defeat ISIL," McDonough told ABC News show "This Week," using an acronym for Islamic State.

On CNN, McDonough said the strategy would be carried out in a "disciplined, thoughtful fashion."

Reacting to the beheading of David Haines, a British hostage, McDonough said, "ISIL will do anything it can to strike terror and fear into its opponents, but, ultimately, that's why we're going to beat them."

A new opinion poll showed American voters also question whether the administration can defeat the extremist group, whose savage methods have included beheading two American journalists as well as Haines, a British aid worker.

A House vote could take place as soon as Tuesday on Obama's request for US$ 500 million to arm and train moderate Syrian rebels, one part of his program. McDonough told "Fox News Sunday" he was pleased with progress on convincing lawmakers to vote for the plan.

Republican Representative Michael McCaul, who chairs the House Committee on Homeland Security, told CBS's "Face the Nation" it was important to authorize the air strikes, particularly on Syria, but Obama was late to respond to the threat.

"It's catch-up time trying to get a coalition together and a strategy together," he said.

Senator Lindsey Graham, a leading Republican voice on foreign policy, said on "Fox News Sunday" that it was "disingenuous and delusional" of the administration to think that it could rely on air power alone to defeat Islamic State.

"We're fighting a terrorist army, not an organization; it's going to take an army to beat an army and this idea that we're never going to have any boots on the ground to defeat them in Syria is fantasy," he said.

An NBC News/Wall Street Journal/Annenberg poll showed that many Americans also harbor doubts about Obama's strategy. Sixty-eight percent of voters said they had "very little" or "just some" confidence Obama would succeed in eliminating Islamic State, although 62 percent backed his plan to take action against the group.

Many of Obama's fellow Democrats are wary of a vote to authorize action. The party, which is struggling to hold a slim majority in the US Senate in the November mid-term elections, has a base of liberal supporters who are strongly anti-war.

US Secretary of State John Kerry will testify before the Senate Foreign Relations Committee on Wednesday and the House Foreign Affairs Committee on Thursday.