Max Boot on Smart Diplomacy:

But Mr. Maliki and other Iraqi political figures expressed exactly the same reservations about immunity in 2008 during the negotiation of the last Status of Forces Agreement. Indeed those concerns were more acute at the time because there were so many more U.S. personnel in Iraq—nearly 150,000, compared with fewer than 50,000 today. So why was it possible for the Bush administration to reach a deal with the Iraqis but not for the Obama administration?

Quite simply it was a matter of will: President Bush really wanted to get a deal done, whereas Mr. Obama did not. Mr. Bush spoke weekly with Mr. Maliki by video teleconference. Mr. Obama had not spoken with Mr. Maliki for months before calling him in late October to announce the end of negotiations. Mr. Obama and his senior aides did not even bother to meet with Iraqi officials at the United Nations General Assembly in September.

The administration didn't even open talks on renewing the Status of Forces Agreement until this summer, a few months before U.S. troops would have to start shuttering their remaining bases to pull out by Dec. 31. The previous agreement, in 2008, took a year to negotiate.

The recent negotiations were jinxed from the start by the insistence of State Department and Pentagon lawyers that any immunity provisions be ratified by the Iraqi parliament—something that the U.S. hadn't insisted on in 2008 and that would be almost impossible to get today. In many other countries, including throughout the Arab world, U.S. personnel operate under a Memorandum of Understanding that doesn't require parliamentary ratification. Why not in Iraq? Mr. Obama could have chosen to override the lawyers' excessive demands, but he didn't.