Obama said at a news conference in Chicago at the conclusion of the two-day NATO Summit that a decade of presence in a foreign country can not only cause a strain on the troops but also to the local population "which at a point is going to be very sensitive about its own sovereignty".
"Frankly, the large footprint that we have in Afghanistan over time can be counter-productive," Obama said endorsing the 2014 withdrawal timetable.
In Chicago, leaders of over 60 countries declared that the mission of the UN-mandated International Security Assistance Force (ISAF) for Afghanistan would end in 2014, and NATO would have a new mission and role in Afghanistan after 2013 when all the international forces withdraw and Afghan security forces take over the mantle of the nation's security.
Obama agreed that while there were risks and challenges involved with the plan but it was time the Afghan security forces start taking responsibility for their country.
"I think it is the appropriate strategy whereby we can achieve a stable Afghanistan that won't be perfect, we can pull back our troops in a responsible way and we can start rebuilding America and making some of the massive investments we've been making in Afghanistan here back home, putting people back to work, retraining workers, rebuilding our schools, investing in science and technology, developing our business climate," he said.