Transcript for General Campbell: Terrorist Threat Will Continue to Grow in Afghanistan if Left Unchecked
U.S. Rescue mission in Iraq where the first American was killed since the battle against Isis began last year. That just comes despite president Obama's claim that Americans would not be involved in a combat role on the ground in Iraq or Afghanistan. Martha Raddatz was there to see what that noncombat role really looks like. Reporter: This dramatic video taken by kurdish special operations forces shows that deadly, daring raid and the freeing of hostages, one after another. Five U.S. Helicopters carried kurdish troops and 30 U.S. Special operations soldiers to the isis-held facility. A firefight broke out. Delta force team leader Joshua wheeler playing a pivotal role, up to 20 Isis militants were killed and 70 hostages rescued. But master sergeant wheeler, a highly decorated father of four, was shot dead. Wheeler had survived 14 tours in Iraq and Afghanistan, but it was this train and assist mission, a mission that was not supposed to involve combat that ultimately took his life. That's an inherent risk that we ask people to assume, again, it wasn't part of the plan, but it was something that he did and I'm immensely proud that he did that. Reporter: The train and assist mission in Iraq is much the same as the one president Obama described for Afghanistan earlier this month. Our troops aren't engaged in major ground combat against the Taliban. Reporter: Afghans who need a lot of help and this is what a noncombat mission looks like at bagram airfield, I'm surrounded by F-16s. We got a c-17 coming in right now. In just the last six months alone, U.S. Warplanes have flown 2500 sorties, 11,000 hours. 24/7 days a week. We deployed over 200 times here, expanded 20 rounds. Reporter: And there are armed unmanned aircraft operating as well. So, if you saw an enemy, you would alert the convoy but possibly fire on the enemy? If we needed to, yes, we would. Reporter: And the biggest threat, ieds, the homemade bombs. The number just this year, astoni astonishing. Probably around 5,000 range. Reporter: Teams training Afghans to counter those ieds, the calling card of the Taliban, the group still a major presence here after 14 years of fighting. General John Campbell is the commander of the mission in Afghanistan. The united nations says that one-fifth of the country is either controlled or contested by the Taliban? The Taliban have been fighting this, it's been a very tough fighting season. Reporter: Campbell has had to deal with these threats even as the U.S. Has been drawing down troops. Reporter: What difference does that make for you, commander? I lose eyes and ears up here that give me indications and early warnings of potential enemy movements, enemy attacks. Reporter: Less intelligence about the enemy worries Afghanistan's national security adviser as well. So, they are not as watched as they used to be. That has given them the ability to fight in larger formations. Reporter: And it's not just the Taliban, U.S. Officials here told us that Isis training camps are now operating in Afghanistan. These photos of what looks like an Isis graduation ceremony surfaced on the internet this week. They continue to build their command and control capacity. Reporter: This threat to the homeland from Afghanistan remains? Yeah, absolutely. And left unchecked, I personally believe the sanctuary continue to grow, and there are terrorist groups out there that want to do harm to the United States it's still out there. Reporter: For the people of Afghanistan, the U.S. Troop presence has given some measure of security and most people we talked to want them to stay. We need military help and in the number of soldiers. Reporter: But U.S. Soldiers have come under withering criticism after that deadly air strike on a doctors without borders hospital. Which killed at least 30 staff and patients. The military first said the strike was to aid U.S. Forces in trouble. But then soon backed away from that statement with general Campbell saying, unequivocally that the air strike was a mistake. Can you say with certainty that no U.S. Personnel knew that was a hospital? It was a mistake, because we could not attack a facility like a hospital. Reporter: An investigation is still ongoing. Despite the hospital tragedy, Campbell is confident that the president's decision to halt the drawndown will make a difference. Do you suspect we'll be here even beyond 2017? Many places in the world over the world where we have had a presence, we stayed there, look at Korea, look at Japan, other places, the difference here is that the Afghans want us here.
This transcript has been automatically generated and may not be 100% accurate.