It is a vastly different situation than the one predicted several years ago by top Pentagon and White House officials, who vowed that the military mission would end in 2017.
"I think that Gen.Nicholson has certainly inherited a mission that has sadly gone wildly off course," said Michael Kugelman, an Afghanistan and South Asia expert with the Wilson Center, a think tank in Washington.
That sentiment was echoed recently by the chairman of the Joint Chiefs of Staff, Marine Corps Gen. Joseph Dunford, who commanded the Afghanistan war from 2013 to 2014.
"When we looked at this in 2013, we assumed a certain progression, of ministerial capacity, core-level capabilities, the intelligence enterprise, special operations and aviation," Dunford told reporters on Feb. 29.
"And many of the assumptions we made in 2013 didn't obtain," Dunford said. The Afghan forces still have "capability gaps" and "we are looking at that right now," he added.
"I will be prepared to make recommendations to the secretary as to how we can incorporate the lessons learned from 2015 into more effective operations in 2016," Dunford said.
Nicholson is also likely to consider changes that would make the air campaign more aggressive.
"We have not effectively used our air power against the Taliban," said Marvin Weinbaum, a former State Department official and Afghanistan expert with the Middle East Institute in Washington.
The new general's arrival creates an opportunity for adjusting troop levels and the rules of engagement regarding airstrikes, Weinbaum said.
"It's a good time for it to change. A new guy comes in and he's in a position to say 'I've reviewed this and here is my recommendation.'"
Yet any change is likely to be incremental, even after a new commander-in-chief takes over in January. "I don't think there is a lot of latitude for a great deal of change in policy. Some adjustment here, some there, but it is not a campaign issue," Weinbaum said.
As a colonel, Nicholson led Task Force Spartan, his first big assignment in Afghanistan.
Photo Credit: DoD
"And we've got our hands full in Syria and Iraq and that has got to be a factor," Weinbaum said.
Nicholson, unlike many of his peers who spent years in Iraq, has focused more on Afghanistan during his career. He has spent more than three years total deployed to Afghanistan, including stints as a brigade commander, as the head of Regional Command-South and as director of the Joint Chiefs of Staff's Pakistan-Afghanistan Coordination Cell.
His critics — namely a group of Marines whom Nicholson had ejected from the war zone after a deadly battle near the Pakistan border nine years ago — have questioned the general's selection and overall track record in Afghanistan.
Nicholson's uncle, Jim Nicholson, was also a Vietnam veteran who retired as an Army colonel and later served as the chairman of the Republican National Committee at the time Bush was elected. Jim Nicholson later served as secretary of Veterans Affairs.
Other observers say that Nicholson's background is precisely what's needed at such a tenuous moment in the war.
In his remarks at Wednesday's change-of-command ceremony, Nicholson acknowledged the "tough path" ahead." Then, speaking briefly in Pashto, he said "let us go forward with courage."
Nicholson grew up in a military family with political connections. His father, John "Jack" Nicholson, was an Army one-star general and Vietnam veteran who later served as undersecretary of Veterans Affairs during President George W. Bush's admin.
Nicholson's uncle, Jim Nicholson, was also a Vietnam veteran who retired as an Army colonel and later served as the chairman of the Republican National Committee at the time Bush was elected. Jim Nicholson later served as secretary of veterans affairs.
Andrew Tilghman is the executive editor for Military Times. He is a former Military Times Pentagon reporter and served as a Middle East correspondent for the Stars and Stripes. Before covering the military, he worked as a reporter for the Houston Chronicle in Texas, the Albany Times Union in New York and The Associated Press in Milwaukee.