The war has cost almost 2,300 US lives, billions of dollars, and yielded middling success since President George W. Bush launched it in October 2001. After almost 16 years, the Taliban now controls more territory than it did when the US first entered Afghanistan.
Those factors led candidate Trump to question the US presence there, a stance that recently ousted chief strategist Stephen Bannon endorsed against virtually all the President's senior national security officials, who argued for continued engagement.
But now, after reviewing a series of options, including a complete withdrawal, the President is reportedly set to unveil a broad approach that includes a troop increase of about 4,000. He is expected to cast that step, along with the focus on counterterrorism and Pakistan, as a concrete way of making good on his "America First" commitment to protect the US from terrorism.
"It's not about the numbers," said James Carafano, a vice president for foreign and defense policy at the Heritage Foundation, speaking about the expected increase in troops. "It's where they are and what they're doing that's important."
Alyssa Ayres, a senior fellow for India, Pakistan and South Asia at the Council on Foreign Relations, says that Trump's expected focus on "terrorist sanctuaries in Pakistan" will be crucial. "We can't have a successful state in Afghanistan unless things change in Pakistan," Ayres said.
State Department spokeswoman Heather Nauert said Secretary of State Rex Tillerson spoke Monday with Pakistani Prime Minister Shahid Khaqan Abbasi, Indian Foreign Minister Sushma Swaraj and Afghan Foreign Minister Salahuddin Rabbani to outline how the US would like to work with each country to stabilize South Asia through "a new, integrated regional strategy."
Analysts say the new policy emphasis could re-focus political and military attention on what could be called
the United States' longest-running military conflict
, one that has often seemed like a morass. High-level attention drifted when the US launched the Iraq War. And under President Barack Obama, the US announced a surge alongside a plan to leave -- a step critics considered a huge mistake as it allowed the Taliban to simply wait Washington out.
A troop increase ahead
To this point, "some might say there's been no thought to a truly effective strategy to allow the US and NATO to do damage," said Michael Kugelman, deputy director of the Asia Program at the Wilson Center.
Additional troops, above current levels of about 8,500, would serve very specific purposes, Pentagon officials tell CNN, boosting training, capacity-building and allowing advisers to work more closely with Afghan troops along the front lines.
The increase was effectively approved in June, when Trump gave Defense Secretary James Mattis the go-ahead to boost levels by as many as 3,900 troops. Mattis, however, has waited to act until there was a broader strategic framework to work within.
US commanders would bring in additional advisers to support Afghan special forces, the Afghan air force, and the Afghan army and police professional schools, such as the infantry and artillery schools.
The Afghan government wants coalition backing to double the number of Afghan commandos and special forces, which have been stretched thin. "The Afghan Special Forces have been singled out as the crown jewel -- more disciplined, efficient, effective than any other unit of the Afghan forces, but they've been over extended and overused," Kugelman said.
Pentagon officials estimate the special forces and commandos perform 70% of offensive operations. A few thousand more US troops would the allow for the capacity to focus on the special forces and boost their numbers, which hover around 12,000.
A small surge would also allow US commanders to put more advisers closer to the front line, giving them an enhanced ability to call in airstrikes. Extra troops would also enable commanders to give those advisers more force protection, which would allow them to spend more time embedded with Afghan troops.
"As it currently stands, on any given day, we are only able to advise at about 75% of our capacity because of a lack of force protection for our advisers," one official told CNN.
Additional forces would allow for more expeditionary advisory packages, teams of about 150 to 200 advisers that surge into an area and provide advice, to operate simultaneously throughout the country.
The broader aspects of Trump's Afghanistan policy are expected to focus "very concretely on counterterrorism," Kugelman said, and increasing troops would allow the President to intensify the counterterrorism mission, particularly against ISIS
and al Qaeda, both of which have a presence in the country.
Carafano agrees. "There's always this challenge that there's more targets and leads than you can service with high-end counterterrorism capability," he said.
Trump is also expected to unveil a new approach for dealing with Pakistan in an attempt to squeeze the government to stop giving safe haven to terrorists.
US patience with Islamabad has been running thin. Last year, the Obama administration declined to certify Pakistan was taking sufficient measures against terrorist groups, which allows the US to withhold funds from Islamabad. Mattis took the same step
That same month, the State Department declared that Islamabad still doesn't do enough to crack down on terror groups that attack Afghanistan and US interests there from bases on Pakistan's side of the border.
Groups such as the Afghan Taliban, the Haqqani network, Lashkar e-Tayyiba and Jaish-e-Mohammad continue to operate, train, organize, and raise funds in Pakistan, the State Department said in an annual report on terrorism.
And these groups sometimes operate seemingly without constraint. The group Lashkar e-Tayyiba recently registered themselves as a political party in Pakistan -- despite the fact that they're under a UN terror designation and considered responsible for a terror attack in Mumbai
that killed 164 people, including Americans.
Trump isn't likely to name Pakistan a state sponsor of terrorism, officials said, but other steps, including a cut in US military aid or a reduction in payments for its operations against terrorism, are possible. Congress could also find technical ways to tighten the type of defense equipment authorized for sale to Pakistan, Ayres said.
"They are not making credible efforts to deal with terrorists on their soil," Ayres said. "And absent a change in behavior in Pakistan, we'll continue to have trouble in Afghanistan."
The Embassy of Pakistan did not return calls requesting comment.