Barack Obama warned today that coalition forces in Afghanistan faced months of hard fighting, but said they had started to "reverse the momentum of the insurgency" by taking the fight to the Taliban.
Speaking after a meeting at the White House with the Afghan president, Hamid Karzai, Obama said the deployment of thousands more troops was paying off.
"There are many difficult days ahead in Afghanistan. We face a determined and ruthless enemy but we go forward with confidence," he said.
Obama said the Afghan government and its allies could not hope to win through military means alone but that keeping up the fight against what he called a brutal insurgency was essential as part of a strategy to encourage Taliban supporters to abandon the conflict.
"The incentives for the Taliban to lay down arms and make peace with the Afghan government in part depends on our effectiveness in breaking their momentum militarily, and that's why we put in the additional US troops," he said.
The two leaders papered over the bitter public differences of recent months, in which the Americans made it clear they considered corruption under the Karzai government was alienating much of the population and undermining the fight against the Taliban. The Afghan leader accused the west of wanting a puppet government in Kabul.
Following on from the tone of Karzai's meeting with the US secretary of state, Hillary Clinton, on Tuesday, Obama sought to underplay the divisions.
"A lot of them were simply overstated," said Obama "Obviously there are going to be tensions in such a complicated, difficult environment, in a situation in which on the ground both Afghans and Americans are making enormous sacrifices. "We've had very frank discussions, and President Karzai agrees with me that we can't win through a military strategy alone. That we're going to have to make sure that we have effective governance, capacity building, economic development, in order for us to succeed."
Karzai responded that there had been differences and would continue to be so but that the relationship was strong.