Updated at 6 p.m. ET on Aug. 20
President Trump's calculation about Afghanistan boils down to a familiar question in U.S. national security: Of all the bad options, what's the least worst?
Trump will "provide an update on the path forward" in Afghanistan and South Asia on Monday night at 9 ET, the White House said on Sunday. The president will make the announcement at Fort Myer in Arlington, Va.
Trump, Vice President Pence and other national security team members convened at Camp David on Friday to review the next phase of the nearly 16-year war. Trump tweeted on Saturday that "many decisions" had been made during the meetings, "including on Afghanistan."
Defense Secretary Jim Mattis told reporters Sunday that he is "very comfortable that the strategic process was sufficiently rigorous," according to the Associated Press. But he would not discuss the policy plans ahead of the president.
Trump could authorize a new deployment of more American troops to continue the approach the U.S. has taken all along. Or he could try to shift the burden so that more of it falls on private security contractors. Or he could authorize something like a gradual withdrawal — or cut bait entirely.
None of those choices would bring victory or end the conflict, and each one has its downsides. As the summer wears on, however, observers worry that whatever the Trump administration decides, it's taking too long.
"It is doing just what it should not do," wrote defense scholar Anthony Cordesman of the Center for Strategic and International Studies. "It is letting the situation steadily deteriorate and is losing by negligence and default."
The problem is not new: Afghanistan is a house that can stand only if the United States remains in the corner holding up the roof.
Its government cannot afford the military and security infrastructure built by Washington and other international donors. The Afghan military and police cannot hold their own against the Taliban and other insurgents they've been battling for nearly two decades. Billions of dollars of international aid have been squandered.
The U.S. intelligence community assessed years ago that if or when the United States withdrew its support, the Afghan government would most likely collapse. The question is how badly and how quickly.
A new troop deployment could keep the war on a low boil but preserve the status quo or even claw back some previous security gains — at greater risk to the larger population of American troops and the increased costs associated with a larger troop presence.
Switching to larger numbers of military contractors could usher in an unprecedented new era in which Washington more or less privatized a major arena of national security policy. That might pose fewer risks to American troops, but it would likely still be expensive and certainly still dangerous for the mercenaries who took over.
A withdrawal is the least certain, and potentially most dramatic, of all the options said to be under consideration. The devil, as ever, would be in the details.
President Barack Obama wanted to reduce the American military presence in Afghanistan to just a standard embassy detachment, but he had to backtrack from that plan toward the end of his tenure when it became clear that the dangers were too great from the Taliban and terrorist forces.
Mattis and Pentagon leaders appear to continue to hold that view, as may national security adviser Lt. Gen. H.R. McMaster. They pushed to deploy nearly 4,000 more U.S. troops to Afghanistan earlier this year to join the current force of about 8,500 in helping train the indigenous forces and fight insurgents and terrorists.
Trump and his top political advisers, however, are said to question whether the status quo is worth preserving if it won't bring the war any closer to a satisfactory end. The United States couldn't set the Afghan government up to succeed and defeat its enemies with 100,000 troops under Obama, so a much smaller bump would almost certainly not be decisive.
Trump has been described as bitterly frustrated with the war and his options, to the point where he has aired firing the top U.S. commander in Afghanistan, Gen. John Nicholson. The general so far remains in his job but the White House also has delayed rolling out a new strategy for Afghanistan that was expected early this summer, which was supposed to outline the mission for any additional troops.
Mattis said this week that Nicholson "is our commander in the field, he has the confidence of NATO, he has the confidence of Afghanistan, he has the confidence of the United States."
But there are more signs that Trump is fed up with the generals. He even hosted a group of lower-ranking service members at the White House in July to ask them for their take on what he should do.
"We're going to be getting some ideas because we've been there — it's our longest war — we've been there for many years ... and I want to find out why," he said.
The White House did not disclose what advice the troops gave the president, but Trump and his advisers are said to look hard at this bottom line: If Afghanistan is unwinnable, why prolong the danger to American forces and the cost associated with deploying them?
Why not just rip off the Band-Aid?
Simply deciding to do so would not be enough, however. The White House would need to determine how to achieve its ends.
Trump could let Afghanistan down easy: preserve financial support for the government in Kabul, ask to keep some American warplanes and drones in key bases and continue targeting the most dangerous terrorist groups — but get most U.S. troops out.
Supporters of a withdrawal make the case that decreasing American support for Afghanistan effectively imposes costs on nearby Iran, China and Russia. That could be worth doing for its own sake, in this view — "forcing the countries that do have major strategic interests in the region to take on the burden or live with the consequences," as CSIS's Cordesman wrote.
The Afghan government might have a great deal to say about all this. And it might not agree to permit U.S. forces to keep access to only the bases that Washington wants if American troops are withdrawing from everywhere else.
If that means a breach with Kabul and full-scale "retrograde," as military planners would say, it would start the clock on a dark new era for Afghanistan. Taliban and terrorist insurgents would press their gains across the country and put intense new pressure on the more populated areas controlled by the central government.
But the terrorism threat in 2017 is different from 2001, when the U.S. invaded. Extremist groups have proliferated in the Middle East and North Africa, but they are divided and, say U.S. national security officials, less capable of launching a major attack.
Former CIA Director John Brennan told an audience at the Aspen Security Forum that although homegrown extremists or small-scale attacks remain dangerous, he believes the U.S. and its allies could disrupt or prevent something as large as another Sept. 11 plot.
Or so the U.S. and Western governments might hope. In terms of terrorism, abandoning Afghanistan might amount to a roll of the dice.
Separate from the geopolitical and security implications, the biggest consideration for Trump and his advisers are the politics. How much do Americans care?
If the old conventional wisdom was that a president didn't want to "lose" Afghanistan in the way that the U.S. "lost" Vietnam — or the way critics blamed Obama for the rise of the Islamic State after the withdrawal of American forces from Iraq in 2011 — does that still apply?
Most Americans are disconnected from the war in Afghanistan. Only a small minority have served there or know someone who has. And even though U.S. casualties do continue — 10 service members have been killed in Afghanistan so far this year — the war keeps well off the front page and almost never gets onto TV. Obama himself claimed to have "ended" combat in Afghanistan.
So the question for Trump is whether he would pay any political price for pulling the plug on a conflict that many Americans already ignore, or whether the risks from a crumbling Afghanistan would be so great it's wiser to keep the war going behind the scenes.
Mattis told reporters on Aug. 14 the research and analysis behind the menu of choices for Trump was complete. What remained, he said, was for the president to pick.
"We're sharpening each one of the options so you can see the pluses and minuses of each one, so that there's no longer any new data you're going to get," Mattis said. "Now just make the decision."