To be sure, some troops from NATO countries, led by the United States, will likely stay behind after 2014 – both to train Afghans and act as a hedge against the Taliban's return. The summit will try to iron out some of those details.
But perhaps even more crucial – certainly for Afghanistan itself – is the question of who will foot the bill for Afghans to protect themselves. Afghanistan does not have remotely enough money to defend itself. Left alone, it could afford to pay about 30,000 soldiers and police officers. Currently, with international aid, it has more than 300,000 – a number that some experts say is too low.
As a result, much of the Chicago summit will be a passing of the hat for Afghanistan. With NATO countries war-weary and economically strapped, the commitments may not exactly fill that cup to overflowing.
It points to a NATO role in Afghanistan that will continue for years after the end of the international combat mission in 2014, but at a much-reduced and still uncertain level. And it suggests that for all the heady words spoken by NATO leaders, funding and troop pledges for an event still two years away are likely to remain vague.
The two-day meeting "will be something of a tin-cup exercise and should give us some idea of what the [NATO] coalition countries' post-2014 commitments to Afghanistan will look like," says Heather Conley, director of the Europe program at the Center for Strategic and International Studies in Washington.
In a clear reflection of this reduced commitment to Afghanistan, the gathering is expected to endorse the scaling back of the Afghan National Security Forces. Army and national police forces once envisioned to hover around 350,000 personnel for years after NATO's departure are now seen as gradually scaling back to something over 200,000 by 2018.
"The idea is to gradually reduce the size of the Afghan forces to make them more affordable," says James Dobbins, a former US Afghanistan envoy and now director of the International Security and Defense Policy Center at the RAND Corp. in Arlington, Va.
US share: about $2 billion per year
Pre-summit discussions among NATO countries resulted in a consensus that foresees the US picking up "the largest part of the cost," Ambassador Dobbins says, with other countries making up the rest. That US share is expected to be about $2 billion a year, with other countries making up the difference of an annual bill of about $4 billion.
Afghan President Hamid Karzai has indicated that he doesn't think the $4 billion will be enough. During the recent surge, the US was spending about $100 billion a year to maintain its force of 100,000 troops.
Dobbins says he expects the pledges at Chicago to remain general, in part because countries are reluctant to make specific funding commitments for what is still a few years off. Moreover, NATO nations are concerned that promised gains in Afghanistan have not panned out.
"The thinking was that the US surge would kick the stuffing out of the Taliban, they would thus be on the road to defeat, and we'd be handing off a much simpler job," says Stephen Biddle, senior fellow for defense policy at the Council on Foreign Relations in Washington. "Instead, in 2015 we'll be handing off a stalemate and a war that in fact is not going to be ending anytime soon."
The reluctance to pledge long-term commitments to Afghanistan extends to the US as well. Some members of Congress are already warning that there is likely to be a dwindling appetite for picking up a $2 billion annual check for the Afghan security forces after 2014 – even as the White House counters that the price tag is a small fraction of the $88 billion the Pentagon expects to spend in Afghanistan in 2013.
Yet even if NATO countries stick to vague commitments, which will be enough to satisfy the modest goal the US has set for Chicago, regional experts say, the US wants to make a decade-long commitment to troop levels and funding in Afghanistan, and it wants to make sure it is not left on its own.
"What [the US wants] is for NATO to endorse that" general commitment, says David Pollock, a former State Department planning staff official now at the Washington Institute for Near East Policy. But with national budgets tight and with "people convinced that Afghanistan's long-term success is a long shot," he says that "at best [the US] will get a statement of long-term goals – without any long-term commitments."
'We'll be handing off a stalemate'
"That was definitely a setup for the NATO summit, to underline the message that 'the US has done its part, so now you, too, should stand up,' " Dobbins says.
But some analysts doubt that the agreement, which is short on specific US commitments to Afghanistan, will have any impact on the summit.
"The US having failed to sign the SPA by Chicago would have been seriously problematic, but the converse doesn't hold, largely because it commits people to so little," Mr. Biddle says.
What could come from Chicago is a concrete decision formally to shift NATO's mission from combat to training ahead of schedule – in 2013. That transition has already been taking place, Biddle notes, but formalizing it and suggesting that the conditions exist to speed it up could create the perception that NATO is in the mopping-up phase, placating voters and giving NATO members political cover to stay involved a little longer.
"The beauty of changing the mission is that it leaves the political top cover for the allies to stay," Biddle says.
No aura of 'mission accomplished'
Such a maneuver could become even more of an imperative after the election to the French presidency of François Hollande, who promised to have French troops out of Afghanistan by around the end of this year.
Whatever is agreed to in Chicago, no one expects the aura of "mission accomplished" that permeated Mr. Obama's brief mission to Kabul.
Many of America's NATO partners want little to do with Afghanistan, but they also want to stay on the good side of the US and to keep the US committed to the alliance. The result is that coalition countries are likely to come through eventually with commitments, but they will be modest and have more to do with maintaining good relations with the US than with Afghanistan.
NATO countries "will calculate that they can scale down, because they can stay on our good side practically without being" in Afghanistan, says the Washington Institute's Mr. Pollock. Vague talk of long-term commitments aside, he adds, "the drift is to quietly close this chapter in NATO's history."