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President Obama greets U.S. troops at Bagram in Afghanistan

Mandel Nganmandel / AFP - Getty Images

President Barack Obama greets troops during a visit to Afghanistan's Bagram Air Field on May 1. Obama signed a US-Afghanistan strategic partnership agreement during his unannounced visit to the country.

President Barack Obama and Hamid Karzai signed an agreement that provides a framework for a lasting U.S. commitment to Afghanistan at the presidential palace in Kabul shortly after the U.S. president arrived in Afghanistan on Tuesday on an unannounced visit.

The president then traveled from Kabul back to the Bagram Air Field to spend time with the troops.

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During an unannounced trip to Afghanistan, President Barack Obama said the U.S. and Afghanistan are now committed to replacing war with peace. The new agreement will establish a framework for U.S. involvement in Afghanistan from 2014 to 2024, and pledge economic and security resources from the U.S. NBC's Chuck Todd reports.

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More than ten years after the beginning of the war, Afghanistan faces external pressure to reform as well as ongoing internal conflicts.