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Joe Votel was only a few weeks into his new job as commander of the 75th Ranger Regiment, the US Army’s elite special operations force, when Al Qaeda hijackers attacked New York.
At his base in Fort Benning, in the southern state of Georgia, his secretary came into his office and told him to switch on the TV.
“It was confusion and then shock of what was happening,” the now retired four-star general recalled, speaking to The National from his home in St. Paul, Minnesota.
Then came the “realisation that everything had kind of changed on that day. We knew things were going to be different. We didn't know exactly how.”
In the two decades since the September 11, 2001 attacks, Gen Votel’s career followed the arc of America’s military response.
Having retired in 2019, he is now watching aghast as Afghanistan unravels at breakneck speed and is reflecting on some of the missed opportunities from America’s so-called War on Terror.
“We need to be level with the American people in terms of how hard these things are,” Gen Votel said when asked what lessons could be drawn from the US invasions of Iraq and Afghanistan.
“Another thing that ought to be learned out of this is really the limits of the military…. There has been a belief by our policymakers and others that if we just continue to drop enough bombs, provide enough troops … then we can turn this around.
“That's an important part of this, but the military is insufficient, in and of itself, to accomplish strategic objectives like we had in Afghanistan.”
The former commando, who now is a distinguished senior fellow on national security at the Middle East Institute, was one of the first officers to parachute into Afghanistan during the US-led invasion of October 2001.
Years later -- after heading the Special Operations Command -- he ran the Pentagon’s Central Command (Centcom) that oversees US operations across Afghanistan and the Middle East.
Early on in the Afghanistan war, the US and its main ally Britain maintained a “light touch” approach, relying on air power and small numbers of commandos to topple the Taliban.
Special forces troops were quick to achieve this goal, but the Pentagon would not allow them to push their strategic advantage, instead relying on more air strikes and untrained Afghan militias.
“If we'd have been more aggressive ... we could have solidified the situation a bit quicker and brought stability to the country faster, and then move forward on some of the more important governance and other issues that that needed to be addressed,” Gen Votel said.
Vast numbers of Taliban fighters fled to neighbouring Pakistan or rural areas in the south and elsewhere.
Gen Votel recalled the US intelligence community learning of the whereabouts of Osama Bin Laden and other senior Al Qaeda leaders, who were hiding out in the Tora Bora mountainous region of Nangarhar province bordering Pakistan.
“We had an opportunity at Bin Laden, and really to strike a very devastating blow against Al Qaeda in December of 2001,” Gen Votel said.
But “for a variety of reasons, we were unable to capitalise on that. And then, I think our campaign wandered a little bit," he added. Bin Laden crossed into Pakistan and melted into the rugged tribal area.
With Bin Laden’s escape, the Afghan mission was only half complete. The consequences of failing to fully vanquish the Taliban and Al Qaeda early on paved the way for the brutal insurgency that followed.
The diversion of resources and attention to a new invasion has been blamed for many of the ensuing failures of the US mission in Afghanistan.
“Where we made a mistake was not pressing harder. On Afghanistan, we really had the opportunity, when the Taliban were really on the outs there … to start looking at how we were going to re-engage with that part of the population and to solidify the security environment and really press hard against Al Qaeda,” Gen Votel said.
“There was a lot of focus back here in the United States on Iraq and that took a sucked a lot of oxygen out of the air.”
Critics have also pointed to negotiations in Bonn in December 2001 as seeding future conflict. The Taliban were denied a seat at the table as western powers picked their successors.
With no stake in a future government, the Taliban asserted that any “puppet” regime would be illegitimate -- messaging they stuck to for 20 years.
“It took us several years before we'd kind of figured out that we needed to put more emphasis on the ground [in Afghanistan]. Again, a lot of a lot of that was because of our some of our distraction with Iraq,” Gen Votel said.
Over the years, western powers have spent billions of dollars training and equipping Afghanistan’s forces, with some 300,000 national police and soldiers filling the ranks.
Countries like the US insisted the Afghan security forces were strong enough to stand alone, pointing to a nascent air force and elite special forces units as particular success stories.
Afghanistan watchers have for years warned of inherent weaknesses in the Afghan military and police forces, which are beset by corruption, but the pace of the collapse has stunned even sceptics.
The Taliban have taken over most of the country, with Kabul next on their list.
A tide of humanity is descending on the capital as people seek to flee the Taliban onslaught amid reports of executions and the kidnapping of young girls for Taliban brides.
Gen Votel said such an outcome was predictable amid a rushed US withdrawal. The relatively small Nato footprint – and US air power – had been enough to keep the Taliban at bay for years, he said.
“We could have left a small sustainable presence on the ground that would have helped preserve our interests,” he said.
He sees little hope for what comes next.
“I'm sad for the people of Afghanistan. The good people of Afghanistan really deserve an opportunity for peace and stability. I'm disappointed that we weren't able to deliver for them,” he said.
“We had other options available to us here. I'm sad that we have chosen to go in the direction we have.”
All of which leads to the inevitable question: was any of it worth it?
“I've been asked this question several times,” Gen Votel said.
“For a variety of reasons, we have not achieved the political, strategic end state that we would have desired in this. ... I don't think it minimises the service of anybody that was that fought there, that served there, or who had loved ones lost there”.