The War in Afghanistan has gone on for 17 years and counting — and there's no end in sight. In Pulitzer Prize-winning reporter Steve Coll's new book about the history of the war, he investigates how the United States went from the shock of 9/11 to the stalemate we're in now. It's titled "Directorate S: The C.I.A. and America's Secret Wars in Afghanistan and Pakistan," and it focuses on the mistakes made by U.S. intelligence, then and now. His previous book, "Ghost Wars," chronicled Afghanistan's descent into violence and terrorism, starting with the Soviet takeover and ending the day before 9/11.

Coll joined Boston Public Radio to discuss "Directorate S" and what he's learned from covering Afghanistan for 30 years. Below are highlights from the interview. 

On the meaning of the title

Coll: "Directorate S" is the covert action wing of the Pakistani intelligence services, Inter-Services Intelligence, or ISI. We used to work with them, the CIA worked with them in the 1980s ... to defeat the Soviet occupation by arming and funding Islamist Afghan mujahideen guerrillas. After 2001, they went back into action essentially against NATO and the United States, [and] after 2006 or so running the same playbook we had run against the Soviets in the 1980s.

On the mistakes that America repeated in Afghanistan and Iraq

Coll: [The Bush Administration] didn't anticipate the cascading consequences of their invasion. They didn't anticipate the struggle they would have to establish a new democratic government in Iraq. Then — and this happened in Afghanistan at the same time, and is an important part of the story in the book — they were informed by hubris about the rapid success of their initial military operations both in Iraq and Afghanistan.

In both countries, they made the same mistake ... History's lesson is, if you win a war, you better win the peace by incorporating into post-war politics as many of the defeated population as you can. Yes, you can hold leaders of the enemy force accountable. You can try war criminals, the way we did in Germany and Japan. But if you want a stable post-war environment, you can't treat every foot soldier, every lieutenant, as if they were part of the problem forever. But we did that, both in Afghanistan, where we treated every Taliban foot soldier as a candidate for Guantanamo, and shipped off hundreds of them, seeding the bitterness that came back when they came back. We did the same thing in Iraq. We dissolved the Ba'ath Party and disenfranchised, essentially, a big chunk of the population who immediately went to war with us.

We haven't had a diplomatic strategy to complement the military strategy in years. Certainly, there's no sign of that on the horizon now.

On the parallels between Afghanistan and Vietnam

Coll: There's a couple of scenes in the beginning of the Obama Administration in the book where Richard Holbrooke, who was the diplomat who was appointed to try to negotiate some kind of resolution to the Afghan War by President Obama, he gets crosswise with the president. He's kind of a self-dramatizing personality and Obama doesn't like his tones, but one reason he offends the president is he keeps mentioning Vietnam as a cautionary example because Holbrooke was there as a young diplomat. Obama finds this annoying. When I was going back through my notes, I was talking to Holbrooke around this time and he mentioned he had really alienated the president by referring to Vietnam as a framework for making decisions about troop escalations. Then he said, "They shouldn't be so afraid of history." At the time I thought, "Okay, that's a clever line." Now, 10 years on, looking back at that, [it's] very powerful.

On where we are now

The Trump Administration has come in doing the same thing that the Obama Administration did [and] maybe the Bush Administration did when it came in. There's this kind of "thing" in Washington where you come to power and you assume everything the previous administration did was wrong and all their assumptions were wrong. The Trump Administration thinks it has really reset the war in Afghanistan because it has put pressure on Pakistan, withdrawn aid or suspended aid, and loosened the rules of engagement on the battlefield. So they've dropped more bombs and they are maybe more aggressive in combat than the special forces were in the late Obama years ...

But there's 10-15,000 international troops and tens of thousands — but not hundreds of thousands — of capable Afghan security forces. The Afghan army suffers from illiteracy, from poverty, from ethnic factionalism. To think you're going to accomplish on the battlefield with that force what 150,000 of the best infantry in the world couldn't accomplish doesn't seem very plausible.

On what we should do next

My experience of Afghanistan is that Afghans deserve better from us than just to be abandoned. We made promises to the Afghan population that we would support their constitutional restoration, the resurrection of an independent Afghanistan, and we've failed them. To just walk away doesn't seem right. It would almost certainly strengthen the Taliban and the Islamic State.

There are alternatives to the status quo. One would be to carry out a diplomatic and negotiating strategy that was as well-resourced, as high a priority, as our military strategy. This is one of the contradictions that has lasted a decade, which is: every general who goes over for the United States to command the war will say, "There is no purely military solution to this war."... But we only resource military action. We haven't had a diplomatic strategy to complement the military strategy in years. Certainly, there's no sign of that on the horizon now.

Click the audio player above to hear more from Steve Coll.