Brahma Chellaney, The Globe and Mail

Despite the worsening Afghanistan quagmire, this month’s 15th anniversary of the longest war in American history attracted little attention. The raging battles cast a shadow over Afghanistan’s future and highlight the failure of U.S. President Barack Obama’s strategy to gradually wind down the conflict. The war now draws little international attention, except when a major militant attack occurs.

The current situation in Afghanistan is worse than at any time since 2001, when the U.S. invasion helped oust the Taliban from power, forcing them to set up their command-and-control structure in neighboring Pakistan, their creator and steadfast sponsor.

Today, the resurgent Taliban hold more Afghan territory than before, the civilian toll is at a record high and Afghan military casualties are rising to a level that American commanders warn is unsustainable. From sanctuaries in Pakistan and from the Afghan areas they hold, the militants are carrying out increasingly daring attacks, including in the capital Kabul, as illustrated by the recent strike on the American University of Afghanistan.

In declaring war in Afghanistan on September 21, 2001 after the world’s worst terrorist attack in modern history ten days earlier in the United States, President George W. Bush explained why 9/11 was a turning point for America: “Americans have known wars — but for the past 136 years, they have been wars on foreign soil, except for one Sunday in 1941 [Pearl Harbor]. Americans have known the casualties of war — but not at the center of a great city on a peaceful morning. Americans have known surprise attacks — but never before on thousands of civilians. All of this was brought upon us in a single day…”

Yet before he could accomplish his war objectives in Afghanistan, Bush invaded and occupied Iraq — one of the greatest and most-calamitous military misadventures in modern history that destabilized the Middle East and fueled Islamist terrorism.

Obama came to office with the pledge to end the Bush-era wars in Afghanistan and Iraq. In Iraq, he ended the Bush war, only to start a new war in the Syria-Iraq belt.

In Afghanistan, Obama thought that he could end the war simply by declaring it over. This is what he did in December, 2014, when he famously declared that the war “is coming to a responsible conclusion.” But the Afghan Taliban had little interest in peace, despite Washington allowing them to set up a de facto diplomatic mission in Qatar and then trading five senior Taliban leaders jailed at Guantanamo Bay for a captured U.S. Army sergeant.

As a result, Obama repeatedly has had to change his plans in Afghanistan. In July 2011, he declared that by 2014 “the Afghan people will be responsible for their own security,” adding seven months later that, “By the end of next year, our war in Afghanistan will be over.” Then in May 2014, he promised that, “One year later … our military will draw down to a normal embassy presence.”

But just two months ago, he decided to keep 8,400 U.S. troops in Afghanistan indefinitely and leave any withdrawal decision to his successor. Some 26,000 American military contractors also remain in Afghanistan, doing many jobs that troops would normally do, according to the U.S. House Armed Services Committee.

In fact, the deteriorating Afghan security situation has forced Obama to reverse course on ending U.S. combat operations and give the American military wider latitude to support Afghan forces. For example, he has now allowed American troops to accompany regular Afghan troops into combat. He has also allowed greater use of U.S. air power, particularly close air support. It is a clear recognition that his strategy to end the war lies in tatters.

This raises the key question: Why is the U.S. still stuck in the war? In large part, it is because it has fought the war on just one side of the Afghanistan-Pakistan divide and been reluctant to go after the Pakistan-based sanctuaries of the Afghan Taliban and its affiliate, the Haqqani network, which enjoys tacit Pakistani intelligence support.

The U.S. assassination in May of Afghan Taliban chief Akhtar Mohammad Mansour by a drone strike inside Pakistani territory was a rare exception — a one-off decapitation attack that did little to change the military realities on the ground.

Research shows that terrorist or militant groups are generally resilient to the loss of a top leader, unless their cross-border sanctuaries are systematically targeted. Indeed, as Israel’s record and America’s own experiences in Somalia, Syria and Yemen show, decapitation can actually help a militant group to rally grassroots support in its favor and against the side that did the killing.

The fact is that no counterterrorism campaign has ever succeeded when the militants have enjoyed cross-border havens. The Afghan Taliban are unlikely to be defeated or genuinely seek peace as long as they can operate from sanctuaries in Pakistan. Indeed, their battlefield victories give them little incentive to enter into serious peace negotiations.

As for Pakistan, Mansour’s killing near where its borders meet with Iran and Afghanistan exposed years of denials by Pakistani officials that they were sheltering Taliban leaders. Like in the 2011 raid by U.S. Navy SEALs that killed Osama bin Laden, Mansour’s assassination involved the U.S. violating the sovereignty of a country that is one of the largest recipients of American aid.

Although Obama hailed the Mansour killing as “an important milestone,” the decapitation cast an unflattering light on U.S. policy: America took nearly 15 years to carry out its first – and thus far only – drone strike in Pakistan’s sprawling Balochistan province, the seat of the Afghan Taliban’s command-and-control structure.

In order to preserve the option of reaching a Faustian bargain with the Afghan Taliban, the U.S. over the years has concentrated its drone strikes in Pakistan’s Federally Administered Tribal Areas (FATA), often targeting the Pakistani Taliban — the Pakistani military’s nemesis. The U.S. military has failed to disrupt the Haqqani network because Pakistan, with the intent to keep this group’s leadership out of the reach of American drones, has moved these militants from FATA to safe houses in its major cities. Meanwhile, the Afghan Taliban leadership, with the Pakistani military’s acquiescence, has stayed ensconced in Balochistan, located to the south of FATA.

Tellingly, the United States has not designated the Afghan Taliban as a terrorist organization. The Obama White House has engaged in semantic jugglery to explain why the group is missing from the U.S. list of Foreign Terrorist Organizations.

In truth, the Obama administration is willing, as part of a peace deal, to accommodate the medieval Taliban in a power-sharing arrangement in Afghanistan. It assassinated the Taliban leader because he defiantly refused to revive long-paralyzed peace negotiations.

For almost eight years, Obama has pursued the same unsuccessful Afghanistan-related strategy, changing just the tactics. His strategy essentially has sought to use inducements to prod the Pakistani military and its rogue Inter-Services Intelligence agency to go after the Haqqani network and get the Afghan Taliban to agree to a peace deal. The inducements have ranged from billions of dollars in military aid to the supply of lethal weapons that could eventually be used against India.

However, the carrots-without-sticks approach has only encouraged the Pakistani military to run with the hare and hunt with the hounds.

Barack Obama’s successor will have to make some difficult choices on Afghanistan. To do so, she or he will have to face up to a stark truth: The war in Afghanistan can only be won in Pakistan. With the Afghan government’s hold on many districts looking increasingly tenuous, the next president, however, will not have the time like President Obama to experiment.

Brahma Chellaney is a geostrategist and the author of nine books, including, most recently, “Water, Peace, and War” (Rowman & Littlefield).

© The Globe and Mail, 2016.