Washington DC, United States - When Barack Obama ran for president as an anti-war candidate in 2008 he surged to victory on a wave of dissatisfaction with the outgoing Bush administration's faulty "war on terror".
Obama promised a war-weary American public he would withdraw US forces from Iraq and Afghanistan and pledged to close the military prison camp at Guantanamo Bay, Cuba.
It hasn't happened the way Obama hoped.
He withdrew troops from Iraq only to be forced to return as the Iraqi army collapsed. US forces are scheduled to draw down in Afghanistan by the end of 2016, but Obama is under increasing pressure to revisit that plan.
Guantanamo is still open.
Now with the submission last week of a war resolution to a divided, sceptical US Congress, Obama is reluctantly reversing course.
He is asking an equivocal American public to go to war against the Islamic State of Iraq and the Levant (ISIL) with a promise that it will be limited.
Amid the political controversy, at issue in practical terms, is whether and how the US will deploy Special Operations Forces on the ground, in addition to the ongoing aerial bombing campaign that began in August.
And, another key unresolved policy question remains - what to do about the regime of Bashar al-Assad in Syria, analysts and lawmakers say.
"A lot of this comes down to whether ground troops can be used," Phillip Lohaus, research fellow at the American Enterprise Institute and a former military counterterrorism analyst, told Al Jazeera.
"There have been some hints that Special Operations Forces will be used. Whether that happens or not depends on how the debate over this resolution works out."
Obama's plan to rout the group relies on cooperation with local forces in Iraq combined with American air power and advisers.
In Syria, the US is planning to train the so-called "moderate" Arab forces to take on ISIL. Those moderate forces in Syria would pose a threat to Assad creating a complication that Obama's resolution for the lawmakers doesn't address.
"It will be a common-sense approach to have boots-on-the-ground," said Senator Bill Nelson, a senior US Democrat who voted for the former President George W Bush's war against Iraq in 2003.
With backing from most Republicans who want to see a hard-line approach to ISIL, Congress is likely to give Obama the authority he wants and more.
Opposition will come from the anti-war wing of the president's own Democratic Party.
"Obviously we need to give the president the flexibility with regard to Special Operations Forces and forward air controllers. Large standing armies like in Iraq, that's not going to be authorised," Nelson said.
Ken Gude is a senior fellow for national security at the Center for American Progress, a Washington-based think-tank closely allied with the White House.
"There's a very difficult balance between what liberals want and what conservatives want that the administration and Congress need to work through if they are going to get this authorisation," said Gude.
Obsolete regulations, new threats
Under the US Constitution, to wage pre-emptive war against foreign enemies, American presidents are required to obtain authorisation from Congress. After the September 11, 2001, al-Qaeda attacks, Congress gave President Bush carte blanche to pursue the group.
A year later, the Bush administration used discredited claims about Saddam Hussein's alleged chemical and nuclear weapons programme, as well as associations with al-Qaeda, to win authority from Congress to invade Iraq.
This was a popular move at first, but many Americans turned against the war as Bush faltered, the pre-war "weapons of mass destruction" intelligence proved false, and the US occupation began to look like an unwinnable quagmire.
Obama's new request signals a significant refocusing of the US military engagement in the Middle East. It's a recognition that the war resolutions Congress passed in 2001 and 2002 are no longer applicable.
"They are both obsolete," said Representative Darrell Issa, a California Republican. "Al-Qaeda as we knew it is no longer al-Qaeda as we know it now."
With ISIL as the new threat, Obama's war request is short. It is limited to three years. There are no geographic restrictions on striking ISIL and associated forces wherever they may be.
But, importantly, an army of occupation is prohibited.
Equally important in Washington is what the resolution doesn't say, notably on Syria.
"The first thing I want to understand is how he plans to conduct the operations in Syria towards a success when there is no plausible way that has been laid out at this time to be successful," said Republican Senator Bob Corker, who will chair the Senate Foreign Relations Committee's drafting of the resolution.
A key concern voiced by Republicans and analysts is that US military action in Iraq and Syria under Obama's resolution is likely to result only in containment of ISIL, not its defeat and destruction.
"If you train the Free Syrian Army, which we are doing, and you send them in to fight ISIL, they're going to go after Assad as well because he is responsible for killing 210,000 of their relatives and countrymen," Senator Lindsey Graham, a leading Republican proponent of US military action, told Al Jazeera.
"If you don't have a strategy to deal with Assad's air power, he will surely kill the army we train."
Obama's former ambassador to Afghanistan, James B Cunningham, told the Senate Armed Services Committee: "It doesn't seem possible to me that a moderate Syrian fighting force is going to be ... put together quickly or easily. It is also going to require outside support."
Republicans, who control Congress, say they will seek to amend Obama's war charter by adding an option to take eventual military action against Assad without specifically targeting Damascus now.
Obama administration officials have told lawmakers privately they do not want to attack Assad's regime out of a reluctance to challenge Tehran, which has backed Assad in Syria's civil war with weapons, troops and money.
This whole thing has sort of a surreal quality about it. Why are we even doing it? No one is going to be happy.
Instead, Obama administration officials have suggested Assad's departure would come through a political process yet to be determined.
Russia and the United Nations have proposed talks between Assad and the Syrian opposition that the US has supported.
While unsuccessful so far, the diplomatic moves signal the Obama White House may view Assad as part of a solution to the humanitarian crisis in Syria, and Assad has stated in recent interviews with Western media that he would be open to reconciliation.
"The American people and the US Congress are not going to authorise the overthrow of the Assad regime. It just isn't going to happen," Gude said.
Some Democrats oppose what they say has become a permanent US war footing. They will push to repeal the 2001 declaration of unlimited war against al-Qaeda.
While they lack the votes to succeed, the move will drive a larger debate about how the US is refocusing its campaign against ISIL and whether, with the Taliban resurgent, it is withdrawing from Afghanistan too soon.
"Retaining the 9/11 authorisation adds a layer of ambiguity and potential to do things that weren't envisioned in the new authorisation," said Michael O'Hanlon, a senior fellow in foreign policy at Brookings, a liberal-leaning think-tank in Washington.
"This whole thing has sort of a surreal quality about it. Why are we even doing it? No one is going to be happy."
The next president will be faced almost immediately with the challenge of renewing this war authority. The political outlook suggests the continuing debate over the US security role in Middle East will be an issue in the 2016 presidential election.
Source: Al Jazeera