That is a strange omission, because the war in Afghanistan -- a decade and half after the first US soldiers deployed there -- is now, at best, a stalemate, with the Taliban having gained significant ground in recent years.

This week I traveled to Afghanistan, accompanying Gen. Joseph Votel, the commander of U.S. Central Command who oversees America's wars in Afghanistan, Iraq and Syria. What to do about Afghanistan is clearly one of the most urgent decisions that will face the next president.

The Taliban today control territory populated by about 10% of the Afghan population -- about 3 million people -- while the Afghan government controls two-thirds of the population. The rest of the population -- about 6 million -- live in areas where the Taliban and the government are vying for control, according to senior US military officials.

Opium profits

The resurgent Taliban have captured almost all of the key poppy-growing Afghan province of Helmand. If Helmand were a country, it would be the nation with the highest production of opium in the world, as it produces about half of Afghanistan's bumper crop.

The Taliban derive an estimated $3 billion from opium , according to UN officials, money that goes a long way in one of the world's poorest countries. Opium profits help to pay the salaries of what the US military assesses to be a Taliban army of between 25,000 to 30,000 fighters.

On Sunday, the United Nations and the Afghan government jointly released a report predicting that opium production is likely to be up more than 40% in 2016 over 2015.

The Taliban also benefit from the continuing sanctuary they enjoy in neighboring Pakistan. The Taliban are headquartered in the Pakistani province of Balochistan, according to Brigadier Gen. Charles Cleveland, the NATO spokesman in Afghanistan.

Meanwhile, in August, US Secretary of Defense Ashton Carter decided against certifying to Congress that Pakistan is doing enough to rein in the brutal Taliban-affiliated Haqqani network. As a result, $300 million of American funding was not provided to Pakistan for reimbursement for its military operations against other elements of the Taliban based in Pakistan.

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The Haqqani network has been responsible for most of the mass casualty terrorist attacks in the Afghan capital, Kabul, according to Gen. John Nicholson, the overall commander of American and other coalition forces in Afghanistan.

Those attacks have resulted in the closure of many hotels and restaurants catering to Westerners in Kabul and they have also greatly diminished investor confidence in the country. This has contributed to GDP growth of only a meager 1.5% in 2015, according to the World Bank, which is down from a robust 8% half a decade ago when the Taliban were largely on the run.

As a result of the cratering of their economy, many Afghans are voting with their feet and migrating to Europe. Afghans are the second largest group of refugees and emigrants in Europe after the Syrians, totaling more than 400,000 last year, according to the UN.

Photos: Afghans share their messages of peace As the Afghan government and European Union met in Brussels on Wednesday October 5 to discuss the future of Afghanistan, the Norwegian Refugee Council asked Afghans what they'd like to see come from the summit. Here are their answers.

"Please help us to have a good education system," said Hossein Ibrahimi, Principal at Gebreal Boys High School in Herat, north west Afghanistan.

"Many children at the school have to study in simple tents and it makes it hard for the children to concentrate," he said of the school which teaches many internally displaced Afghans returning from Iran."If we give the children a good education, we will be able to build a better future," said Ibrahimi. Hide Caption 1 of 6 Photos: Afghans share their messages of peace "Some fathers say boys have to go to school, girls have to stay at home," said 12-year-old Razia, who is studying at Gabreal Girls High School.

"It's not correct. Girls also have the right to an education. They should study." Hide Caption 2 of 6 Photos: Afghans share their messages of peace Zaria (third from right) and her family recently returned to Afghanistan from Pakistan. However she has not yet been able to attend school.

"I want to be educated and become a doctor," she said, adding "I hope to be able to go to school again." Hide Caption 3 of 6 Photos: Afghans share their messages of peace Ghousuddin, 50, and his wife and five children fled fighting in Helmand and headed for Herat.

In the rush to leave, there was no time to put shoes on his youngest child.

"I wish for peace and security in my country," said Ghousuddin.

"Where shall I go with all these kids? I don't have money to leave my country and ask for asylum in foreign countries." Hide Caption 4 of 6 Photos: Afghans share their messages of peace Nooria's husband was killed three years ago when their home was destroyed during fighting.

"My message to world leaders is that I want them to continue to pay attention to Afghanistan," said the 35 year old.

"If there could be more schools in the area, I would not need to be worried about my children walking a long distance to get to class." Hide Caption 5 of 6 Photos: Afghans share their messages of peace Mother-of-eight Hazargul fled fighting in Badghis and is now living in Shaidaee Settlement in Herat.

"What else can we ask for apart from food?" said the 50 year old.

"My children are small and my husband is paralyzed. I am going out in the city and begging for people to feed my children." Hide Caption 6 of 6

Taliban battlefield success

Following the 2015 announcement of the death of the Taliban founder, Mullah Omar, the leader of the Haqqani network, Siraj Haqqani, was promoted to what is effectively the number two spot in the Taliban. The de facto merger of the Afghan Taliban and the Haqqani network over the past two years has likely been one factor in the increasing battlefield success of the Taliban.

When the Taliban managed to take control of the northern city of Kunduz for a period of two weeks in the fall of 2015, it was a seismic shock to the Afghan political system as it was the first time at any point in the past decade and a half that the Taliban had seized a mid-size Afghan city, albeit for only a relatively short period.

The strategic aim of the Taliban in 2016 remains to seize control of a provincial capital, according to Gen. Nicholson.

To that end, this year the Taliban launched multiple offensives against provincial capitals across the country: In the west against Farah; in the north against Kunduz; in the south against Lashkar Gah in Helmand province, and also against Tarin Kot in Uruzgan province in central Afghanistan.

So far, their goal of conquering one of these provincial capitals has eluded the Taliban, a cause for some degree of faith in the Afghan army, and in particular its special forces, which --- unlike the Iraqi soldiers in 2014 who fled at the mere sight of advancing ISIS columns -- have largely stood their ground against the Taliban. This is why Gen. Nicholson describes the present state of play with the Taliban as an "equilibrium" in favor of the Afghan government.

This is also why , according to U.S. military officials, 5,000 Afghan soldiers and policemen were killed in 2015 alone, which is considerably more than the combined total of all US and other NATO troops killed in Afghanistan since 2001.

US military officials estimate that the casualty rate for the Afghan security services could again be as high this year, which raises the longer-term issue of how sustainable the Afghan army can be if the Taliban maintain their pace of operations.

As a result of the Taliban gains, in June the Obama administration loosened the rules of engagement for using American air power against the Taliban. This has resulted in a significant increase in the number of US airstrikes in recent months, according to Brig. Gen. Cleveland.

How ISIS is faring

ISiS has planted its black flags in eastern Afghanistan. Naming itself Islamic State Khorosan, an ancient name for Afghanistan, the terrorist group -- made up principally of Pakistani Pashtuns and a number of Uzbeks --- had the goal of seizing the eastern city of Jalalabad in Nangarhar province as the capital of their self-styled caliphate, according to Gen. Nicholson.

That plan has not fared well. In July, Afghan commandos with embedded US Special Forces attacked ISIS in Nangarhar province, killing 15% of their forces. About 1,000 ISIS fighters today remain on the battlefield, according to Cleveland.

What to do about the Afghan War should be one of the first priorities of the new president when he or she assumes office in January.

President Barack Obama faced a similar choice when he first assumed office in January 2009; a resurgent Taliban looked like they were about to wrest control of much of southern Afghanistan. Thanks to a surge totaling tens of thousands of US troops ordered by Obama, the Taliban were largely defeated in Afghanistan six years ago.

Now it's deju vu all over again.

Obama administration's mistake

The mistake the Obama administration has made in Afghanistan is to announce a series of putative, total withdrawal dates, none of which have actually happened.

These announcements have tended to undermine the will of the Afghan government and armed forces and have helped to keep Taliban morale up.

The Obama administration had planned to effectively zero out US troops in Afghanistan, but given the Taliban resurgence instead settled on leaving 8,400 soldiers in place by the time the next president takes office. This is the bare-bones figure to keep open key US facilities such as Bagram Air Base, where many of the airstrikes against the Taliban originate.

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The next president can build on NATO's recent pledge to keep supporting the Afghan army to the tune of $15 billion over the next four years by saying that the United States plans to remain in Afghanistan for some indeterminate period of time. Such a plan need not involve a significant number of US combat troops, but it would involve significant numbers of Special Forces to train and advise the Afghan military, as well as intelligence assets and air support.

The next president should point to the Strategic Partnership Agreement that the US has already negotiated with the Afghan government that provides the framework for a long-term American presence until at least 2024.

The new president should also explain that it is in US and Afghan interests for the United States to remain a guarantor of Afghan stability for the foreseeable future. After all, Osama bin Laden hatched the 9/11 plot in Taliban-controlled Afghanistan and an Afghanistan with a newly ascendant Taliban, and a growing ISIS presence, surely is in the interest of neither Afghans nor Americans.