When the United States went to war in Afghanistan in the fall of 2001, the impetus and aims seemed clear. “Make no mistake,” President George W. Bush told reporters on September 11, “the United States will hunt down and punish those responsible for these cowardly attacks.” Within days, American bombs began to rain down on Kabul, Kandahar, and Jalalabad, in an effort to smoke out Osama bin Laden and cripple the Taliban regime that harbored him. In a matter of weeks, Kabul had fallen to coalition forces, the Taliban were on the run, and Hamid Karzai was sworn in as the leader of a new interim government. A swift victory appeared all but assured.

Today, 15 years after the invasion began, Afghanistan has turned into America’s longest war. More than 2,300 American troops have died in the conflict, which has cost U.S. taxpayers $686 billion. As a candidate, Barack Obama vowed that we would quickly “finish the job” in Afghanistan. Instead, Obama has presided over a war that went from dismal to disastrous. According to the Special Inspector General for Afghanistan Reconstruction, the Taliban gained ground this year, while the government in Kabul grows weaker. In July, Obama announced that the United States will leave 8,400 troops in Afghanistan—up from the 5,500 he originally called for. By almost any measure, we are moving backwards.

When the conflict began, no one guessed that America would become tangled in a forever war. As a candidate for president, Bush had famously derided the concept of nation-building. The mission in Afghanistan was supposed to be limited in scope: We would go in, get rid of the bad guys, and get out. “For the first time in our history,” Vice President Dick Cheney remarked on October 18, 2001, eleven days after the start of the war, “we will probably suffer more casualties here at home in America than will our troops overseas.” General Tommy Franks, the head of U.S. Central Command, said early on that the war was not about “occupying major strategic terrain,” and therefore offered “the easiest exit strategy we’ve had in years.”

Almost immediately, however, our ambitions metastasized. A month after the war began, First Lady Laura Bush framed the fight against terrorism as a fight for the “rights and dignity of women.” Her speech inspired a long procession of gender initiatives, and scores of Afghan women became pilots, police officers, soldiers, lawmakers, judges, and teachers. Millions of Afghan girls now attend school. Yet it remains common to hear of Afghan women who have been stoned to death, attacked with acid, or beaten by relatives. According to a report by the British government, more than 5,000 cases of violence against Afghan women—including 241 murders—were reported in the first half of this year.

Other initiatives have followed a similar trajectory. Each country in the U.S.-led coalition was assigned a project. Germany was tasked with police reform. Italy would overhaul the justice system. The United Kingdom was put in charge of counter-narcotics. But the fragmented approach further splintered the Afghan state. “Instead of responding to the needs of the population, the initiatives answered the objectives and agendas of the international sponsors,” says Timor Sharan, a senior analyst at the International Crisis Group. Today, police corruption is widespread, access to justice remains wildly uneven, and Afghanistan is still the world’s leading producer of opium.

The United States has spent $113 billion on reconstruction efforts: building schools, installing irrigation systems, funding anticorruption campaigns. Yet billions of dollars were wasted on projects that were never completed or have fallen into disrepair. The failure is particularly clear in rural Afghanistan, where over 70 percent of the population lives. Much of the money for building and employment projects, according to Sharan, was funneled into urban areas at the expense of more remote regions, fostering resentment and contributing to the ongoing civil war. In Kandahar, for example, the security and stability of the city has come at the expense of rural residents, who are routinely discriminated against by the powerful police commander, Abdul Raziq, who has been accused of running a police state.

It is almost hard to remember now that in May 2003, Defense Secretary Donald Rumsfeld landed in Kabul and declared that major combat operations in Afghanistan were officially over. At the time there were just 8,000 American troops on the ground. As the situation deteriorated, however, the U.S. presence ramped up. By 2007, there were 25,000 troops in Afghanistan—but the added firepower only made things worse. The next year was the deadliest of the war so far: More than 150 American troops died, along with more than 2,000 Afghan civilians, many of them killed by coalition air strikes.

The next year, shortly after taking office, Obama announced a surge of 21,000 troops, bringing the total number of U.S. forces in Afghanistan to more than 50,000. That December, he announced he was sending 30,000 more. By August 2010, the number of U.S. troops reached 100,000. Afghans, meanwhile, took advantage of Western forces to settle personal vendettas. The Alakozai clan, for example, convinced U.S. forces to crack down on the rival Chowkazai clan by claiming they were aligned with the Taliban.

At the end of 2014, with an eye on his legacy, Obama declared victory in Afghanistan. “The longest war in American history,” he insisted, “is coming to a responsible conclusion.” Despite the continued presence of U.S. troops, the war receives little attention in the media: There are just over a dozen full-time foreign correspondents stationed in Kabul, down from hundreds at the height of the war. The major TV networks have closed their offices, and newspapers have whittled down their staffs. Deteriorating security has made it harder to go out on reporting trips. The bacchanal of the expat community is a thing of the past, which is good—such excess was long a point of contention for Afghans, who viewed it as a sign of the international community’s wastefulness. Many of those who remain have moved inside the secure walls of the Green Zone in Kabul, along with the embassies and government agencies.

Afghanistan, meanwhile, continues to unravel. The unchecked flow of foreign dollars has made the country’s power brokers rich, resurrecting the widespread discontent that gave rise to the Taliban. And the Afghan National Defense and Security Forces—supported by more than $68 billion in U.S. tax dollars—have proven unable to hold their ground. When Kunduz fell back under Taliban control last fall, government forces deserted en masse. Lashkar Gah, the capital of Helmand Province, is teetering on the verge of collapse: The Afghan government controls only a fourth of the province, and some 30,000 civilians have been displaced, creating a humanitarian crisis. “Families, children, women, all have to sleep on the streets,” says Omar Zawak, a spokesman for the provincial governor. “There is a shortage of food and clean water.” Since 2009—the first year the United Nations began keeping records—the war has claimed the lives of 63,934 civilians.

Before the war started, Mullah Omar, the one-eyed Taliban leader, told a visiting Pakistani official that Osama bin Laden was an unwelcome guest of the Taliban regime. He did not want his government to become embroiled in bin Laden’s global jihad, but the Pashtun code of honor demanded that he host the Al Qaeda leader with grace. “He is like a bone stuck in my throat,” Omar complained. “I can’t swallow it, nor can I get it out!”

Afghanistan may have begun as a “war of necessity,” as Obama once put it—a forceful and targeted response to the attacks of September 11. But today, after 15 years, it’s a catastrophe from which we cannot seem to free ourselves. Osama bin Laden has been dead for five years. But Afghanistan remains the bone stuck in America’s throat.