The NATO summit opening in Chicago Sunday will be dominated by discussion of the alliance's transition out of a combat role in Afghanistan to an advisory one, and particularly, who is going to foot the bill in a global climate of fiscal austerity to make it go smoothly.

The United States, with nearly 90,000 of the 130,000 NATO troops deployed in Afghanistan, has the largest stake in ending the war and ensuring that Afghan security forces will be able to take over and maintain stability in a country balkanized by decades of conflict that extends back long before the 2001 U.S.-led invasion.

With the majority of NATO combat troops expected to be withdrawn by the end of 2014, the main issue will be financing Afghan security forces to the tune of some $4.1 billion, a third of which the U.S. is asking its NATO partners to put up.

This has many NATO allies across the Atlantic figuratively shrugging their shoulders as the European debt crisis forces governments to slash their military budgets, while the U.S. is itself planning to cut $487 billion in defense spending.

Initial projections for the required size of the Afghan army placed numbers at 350,000 troops at an estimated cost of $7 billion a year, the Associated Press reported. That number has now been dropped to 230,000 due to fiscal constraints, leaving a deficit in Afghanistan's security needs.

The Afghan government does not have the funds to support even the reduced troop amount and will depend on NATO for assistance.

Public support for the war in the U.S. and Europe is at an all-time low across the board, and some countries would like to pull out sooner than 2014 and are reluctant to fund Afghan forces after the withdrawal, particularly as their countries are focused on domestic spending issues.

Newly elected French President Francois Hollande has pledged to pull out his country's 3,400 troops by the end of this year, prompting a backlash from the U.S. and Britain, a point of tension that will no doubt be addressed in Chicago.

Pakistan Expected To End NATO Blockade

Pakistan's President Asif Ali Zardari has announced that he will also attend the summit, though his country is not a NATO member state.

Zardari is expected negotiate the reopening of its border with Afghanistan for NATO supply routes, which were closed in November in retaliation for a U.S. drone strike that killed 24 Pakistani soldiers.

The U.S. has already begun talks with Pakistan over the deal, which will most certainly involve financial compensation, though no figures have been disclosed as of Thursday.

Should Islamabad finalize the agreement, there will likely be a backlash among hardline Islamic groups in Pakistan, who were outraged by the drone strikes and have pledged to block supply lines if they are reopened.

We will soon launch a movement to occupy NATO supply routes, Amirul Azeem, a senior leader of Pakistan's largest religious party, Jamaat-e-Islami, said Thursday, the Associated Press reported.