At a hearing Wednesday focused on the strategy for Iraq, the Pentagon conceded that the hope for a multi-sectarian, unified Iraq is becoming a less likely outcome. More likely, they said, is a three-way split of the country.

"Iraq is fractured," said House Armed Services Ranking Member Rep. Adam Smith, D-Wash. "You can make a pretty powerful argument, in fact, that Iraq is no more."

Smith said that while new Prime Minister Haider al-Abadi has pledged support for a multi-sectarian Iraq, the lower-ranking Shiite members who fill out the rest of the government are not committed to that goal. That makes it likely that no matter how many additional U.S. forces are added to recruit Sunnis into the fight, it won't stick.

"Does [Abadi's] writ run through Iraq?" Defense Secretary Ashton Carter responded. "That's what we are waiting to see."

"How do we offer the Sunnis, you know, a reasonable place to be if they don't have some support from Baghdad?" Smith asked. "I think we need to start thinking about it."

Carter said the Defense Department does consider a future that involves three Iraqs, not one. The nation could be split into a Kurdish, Sunni and Shiite territory if Iraq's central government cannot convince Sunnis and Kurds they will be an inclusive and protected part of a unified Iraq.

"What if a multi-sectarian Iraq turns out not to be possible?" Carter said. "That is an important part of our strategy now on the ground.

"If that government can't do what it's supposed to do, then we will still try to enable local ground forces, if they're willing to partner with us, to keep stability in Iraq, but there will not be a single state of Iraq," he added.

In the past 10 months in which the U.S. has sent more than 3,000 U.S. forces to Iraq and conducted airstrikes in Iraq and Syria, the average daily cost of the operation has steadily risen to about $9 million a day. During that time, about 7,000 Iraqis have gone through training provided at one of the five U.S.-run training sites; far less than the 24,000 goal, Carter said.

But the Sunni population, which feels disenfranchised from the Shiite-dominated central government and abandoned during key battles against the Islamic State of Iraq and Syria, still has no reason to believe they will be included and protected, said Rep. Tulsi Gabbard, D-Hawaii.

"I think it's important as we look at this question of what is our strategy to defeat [the Islamic State], it's important that we operate in the world that actually exists, not the one that we hope or we wished could exist or would exist in the future," Gabbard said. "It's important to recognize that while these ideals are good to have, we're operating in the world that exists today.

"Even as we hear rhetoric from Prime Minister Abadi, the reality is that experts, both who wear the uniform and those who have studied the Middle East for a very long time, all say for practical purposes, you have three regions in Iraq. It's a fractured country with the Kurds in the north. The Shias have their stronghold in Baghdad, essentially, and you have the Sunni territories largely to the west."

Smith asked at what point would the U.S. stop trying to force policies on the Iraqi government, if it is unwilling to adopt them.

"So when do we shift that strategy and start building the capabilities of other[s] who will fight?" Smith asked.

In recent weeks President Obama has announced an additional 450 troops to develop Sunni fighters in Anbar province, a move largely seen as the beginning of a second wave of new "lily pad" bases to further build up U.S. presence.

Smith said adding U.S. forces isn't the answer.

"We could drop 200,000 U.S. troops in the middle of this," Smith said. "It wouldn't solve the problem, and I sincerely hope we've learned that lesson and that we don't go deeper and deeper into that, you know, costing more lives and more treasure while only making the problem worse."