After giving him the silent treatment for eight months, President Barack Obama on Tuesday called Afghan President Hamid Karzai. The message? A blunt warning that all U.S. troops will leave his war-torn country by 2015 unless Karzai or his successor sign a bilateral security agreement (BSA) with the United States.

The president had not spoken to Karzai since a June 25, 2013, video conference, and the two had had no contact since a Nov. 21, 2013, letter from Washington to Kabul.

Obama has said repeatedly that he hopes to leave a residual force of some 8,000-12,000 U.S. and NATO troops in Afghanistan to train local security forces and target extremists after most combat forces depart in 2014. But U.S. officials had warned that Obama would pull all American troops absent a BSA that gives American and allied forces immunity from local prosecution.

Karzai refused, saying his successor should be the one to make that commitment. He continued to say no even after Afghanistan’s “loya jirga” assembly of elders approved the agreement.

On Tuesday, Obama bluntly delivered that warning to Karzai himself, according to a White House statement on the call.

Obama told Karzai that he has “asked the Pentagon to ensure that it has adequate plans in place to accomplish an orderly withdrawal by the end of the year should the United States not keep any troops in Afghanistan after 2014.”

“Going after the remnants of core Al Qaeda could be in the interests of the United States and Afghanistan,” the White House readout continued. “Therefore, we will leave open the possibility of concluding a BSA with Afghanistan later this year.”

But “the longer we go without a BSA, the more challenging it will be to plan and execute any U.S. mission” and “the more likely it will be that any post-2014 U.S. mission will be smaller in scale and ambition,” the White House statement said.

Defense Secretary Chuck Hagel hammered home the message in a statement of his own released after the Obama/Karzai call, calling plans for a total pullout “a prudent step.”

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"At President Obama's direction, and with my strong support, the Department of Defense will move ahead with additional contingency planning to ensure adequate plans are in place to accomplish an orderly withdrawal by the end of the year should the United States not keep any troops in Afghanistan after 2014,” Hagel announced.

Hagel also underlined why Obama’s Afghan policy is at a crossroads: Defense ministers from NATO and other countries with a presence in Afghanistan are due to meet in Brussels this week to discuss the future of the alliance’s policy. The White House and its allies face increasing pressure to make decisions about the withdrawal, a complex undertaking requiring significant military resources that can’t all be mobilized instantly.

White House aides have increasingly sounded as frustrated with Karzai as their predecessors in George W. Bush’s administration were. At one point, a senior Bush foreign policy aide joked to reporters that Karzai’s first name should permanently be changed from Hamid to something unprintable here.

Faced with his refusal to sign despite an all-out pressure campaign, the United States is now looking ahead to April elections that will pick Karzai’s successor.

While some prominent Republicans have sharply criticized Obama's handling of Afghanistan, the war-weary U.S. public has largely turned against the conflict, now America's longest war.

While it’s likely too late to repair the Obama/Karzai relationship, it’s not like things were going swimmingly under Bush, either.

At a December 2008 press conference with Bush, the Afghan leader drew nervous laughter when he offered up this description of the relationship between Washington and Kabul:

"Afghanistan will not allow the international community [to] leave it before we are fully on our feet, before we are strong enough to defend our country, before we are powerful enough to have a good economy, and before we have taken from President Bush and the next administration billions and billions of more dollars — no way that they can let you go."

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