Mattis told reporters that he thinks victory is still possible - defined as a political settlement with the Taliban. So the emphasis is on drawing in Taliban elements piecemeal.
Since then, the Taliban has called the government an illegitimate puppet of foreign powers, and demanded to negotiate a peace agreement with the United States instead.
Western diplomats and officials in Kabul say contacts involving intermediaries have been underway with the aim of agreeing on ground rules and potential areas of discussion for possible talks with at least some elements in the Taliban.
Since a year ago, USA forces have increased strikes on Taliban targets, and provided additional assistance to Afghanistan's military.
The military is battling a Taliban insurgency while also fighting Daesh terrorist group's gradual expansion in the country's north and its regular attacks in the capital Kabul.
On Feb. 28, 2018, Ghani offered to allow the Taliban to establish itself as a political party and said he would work to remove sanctions on the militant group, among other incentives, if it joined the government in peace negotiations. They said that while Afghan forces are getting better, the Taliban is likely to threaten Afghan stability this year.
Defense Secretary James Mattis is in Afghanistan Tuesday to discuss the military campaign there and "peeling off" some members of the Taliban to pursue a peace deal with the Afghan government.
Mattis' visit comes a week after United States intelligence officials told Congress that the Taliban was likely to continue to threaten Afghan stability in 2018, despite an improvement in Afghan security forces. "The victory will be a political reconciliation" with the Taliban, which has achieved a stalemate in recent years and shown little interest in conceding to the Kabul government. At that point, he said, Afghanistan would not be "a haven for attacks internationally" as it was when al Qaeda used the country as a launching pad for the attacks of September 11, 2001.
US President Donald Trump's administration has also piled pressure on Pakistan to crack down on militant safe havens on its side of the Afghan-Pakistan border. Mattis noted some positive indications from Islamabad, including Pakistani military operations along the border.
Mattis said the goal is to take advantage of fracturing among the Taliban and peel off those who are exhausted of fighting.
Reconciliation, Mattis said, was "almost an equal priority of my interest going in".
US intelligence officials are predicting the war will remain stalemated as the traditionally most intensive fighting season begins this spring.
The US has a renewed focus on Afghanistan after years of drawdowns under former US president Barack Obama, and talk by top US generals of "not winning" and a "stalemate" in the seemingly intractable conflict. More than 3,000 additional US forces have also arrived in Afghanistan to boost the training and advising of local troops.