Washington: Success of the US campaign against Islamic State militants will come when the group no longer poses a threat to the United States and its allies in the Middle East, a top US official said on Sunday.
US national security advisor Denis McDonough appeared to calibrate President Barack Obama's vow to "degrade and ultimately destroy" the militant group, in spelling out US objectives in an interview with NBC's Meet the Press.
"Success looks like an ISIL that no longer threatens our friends in the region, no longer threatens the United States," he said, using an alternative acronym for the group that has grabbed large areas of Syria and northern Iraq.
"An ISIL that can't accumulate followers, or threaten Muslims in Syria, Iran, Iraq, or otherwise. And that's exactly what success looks like."
Obama's vow in a September 10 speech announcing a stepped-up US air campaign against the militants has drawn a skeptical response, with critics noting that even Al-Qaeda has not been destroyed, despite a 13-year US-led war against it.
War-weary Democrats worry that maximalist US goals could suck the United States back into intractable Middle East ground wars, while Republicans criticized the president for not going far enough, having ruled out US troops on the ground.
Polls show US public sentiment swinging sharply behind US action since the IS posted a videotape showing the beheading of US hostage James Foley. But it is still skeptical that the president's strategy will work.
"This is obviously a complicated effort," said McDonough. "And that's why the president is going about this in a very painstaking, and very prudent fashion.
"That's why the secretary of state is now just continuing his efforts to travel throughout the region to get others to join us in this effort. And that's what we're going to do. We're going to lead an international effort against ISIL. But this is not going to be easy," he said.
Kerry, who is in the region drumming up support for the US-led campaign, said countries in the region and outside have pledged they are ready to help militarily, some even offering troops or to conduct air strikes alongside the United States.
"Every single aspect of the president's (Obama's) strategy, and what is needed to be done in order to accomplish our goal, has been offered by one country or multiple countries and all bases are covered," Kerry said in an interview on CBS's Face the Nation.