President Obama talks about airstrikes against ISIS on the South Lawn of the White House in September 2014. Today, most Americans disapprove of his handling of the situation. (Win McNamee/Getty Images)

In 2008, Barack Obama ran as the presidential candidate opposed to the war in Iraq. In 2011, he said troops would be gone from Iraq by Christmas. In 2012, he was elected to a second term.

In 2015, amid more beheadings and destroyed ancient Iraqi and Syrian cities, an increasing number of Americans disapprove of the president's handling of the Middle East's most pressing terrorism threat, the Islamic State -- a fact that threatens to cast a shadow over Obama's legacy.

According to the latest Washington Post-ABC News poll, 55 percent of Americans disapprove of how the president is handling the increasingly violent terrorist group that's occupying large swaths of Iraq and Syria, while just 31 percent approve. The number of Americans who strongly disapprove of the president's handling of the situation has risen 12 percentage points since The Post and ABC first asked in September.

Even more bad news for Obama: The new survey shows that Americans blame his military policy about as much as they blame the Iraqi army (40 percent to 38 percent) for the problems, and a new CNN/ORC poll finds that Americans blame Obama (44 percent) about as much as George W. Bush (43 percent) for Iraq's problems.

Those numbers break down mostly along partisan line, but not overwhelmingly: 56 percent of Republicans blame Obama's military policy over the Iraqi army, while 58 percent of Democrats put the fault on the Iraqi military. About one-quarter of Democrats blame Obama, and about one-quarter of Republicans blame in the Iraqi army.

The Bush/Obama split is more partisan; 79 percent of Democrats say Bush is to blame, while 75 percent of Republicans place the fault on Obama. But independents in both polls fault the current president more: 43-34 for those who blame Obama over the Iraqi military, and 48-37 for those who blame Obama over Bush.

We could go on, but you get the point.

The numbers underscore the conundrum Obama is facing as he wraps up his final year and a half in office: He pulled the United States out of Iraq -- arguably the issue that won him the Democratic nomination in 2008 -- only to be blamed for the chaos that ensued afterward. And more than any other, the Islamic State's rise risks becoming a defining issue of the Obama foreign policy and the focal point of U.S. foreign policy efforts in the final 18 months of his tenure and beyond.

In September 2014, Obama stood before the nation and promised to wage a campaign "to degrade and eventually defeat" the Islamic State. Since then, the U.S. military has been leading a coalition of countries to conduct limited airstrikes in the region and to arm and train Iraqi soldiers to fight the Islamic State.

"It is going to take some time," Obama told NBC's Savannah Guthrie in February, "because part of our goal has to be to build up capacity inside Iraq, so that it is not American troops on the ground."

That last part is key. After the Iraq war, Obama has made clear that he has no plans to send American combat troops back there. He submitted a resolution for war powers to Congress in February that explicitly would prevent American troops from deploying to Iraq. Congress still has yet to vote on it.

Yet the Islamic State has increased its territorial gains -- a major way the group measures success -- most recently felling the ancient city of Ramadi. The group now controls about one-third of Iraq and Syria.

The Syrian Observatory for Human Rights says the Islamic State is now able to move along a road that connects Aleppo with Turkey. (Reuters)

An overwhelming majority of voters (64 percent) think the United States and its allies are losing the fight, according to another poll this week, from Quinnipiac University.

Republican presidential hopefuls are jumping on Obama's unpopularity and the problems in the Middle East. Perhaps no one stands to benefit more than former Florida governor Jeb Bush, who tried to shift the debate from his brother George W. Bush's war in Iraq (and his oscillations on it) to Obama's battle in Iraq against the Islamic State.

"The focus ought to be on, 'Knowing what you know now, Mr. President, should you have kept 10,000 troops in Iraq?' " Jeb Bush said last month.

Other GOP candidates are also stepping back from the Iraq war, which has now matched its lowest approval rating ever among the American public: In the new Washington Post-ABC poll, just 33 percent say they think it was worth fighting.

In other words, there is plenty of unhappiness and plenty of blame to go around -- including increasingly for Obama.