Tonight, ABC World News aired an interview with Apple CEO Tim Cook, with the conversation focused on the ongoing encryption battle between the iPhone manufacturer and federal authorities. But it turns out what viewers saw on TV was only a small portion; the full-length interview runs just short of a half hour. It's rare to see Cook in this sort of lengthy, uninterrupted exchange.

He acknowledges that Apple is actually working against public opinion in its refusal to concede to the FBI's wishes. "This is not about a poll," he said. "This is about the future." Cook told David Muir that he's received many "heartwarming" letters from the public — including military veterans — encouraging Apple to hold its ground. And he also voiced concern about some of the worst-case scenarios that privacy advocates believe could stem from Apple caving to the government's demands.

If a court can ask us to write this piece of software, think about what else they could ask us to write. Maybe it’s an operating system for surveillance. Maybe it’s the ability for law enforcement to turn on the camera. I mean, I don’t know where this stops. But I do know this is not what should be happening in this country. This is not what should be happening in America. If there should be a law that compels us to do it, it should be passed out in the open, and the people of America should get a voice in that. The right place for that debate to occur is in Congress.

Included below are other excerpts, but the whole interview — filmed inside Cook's own office — is absolutely worth watching. Cook revealed that he intends to speak with President Obama regarding the ongoing case, saying "I’m going to ask for his help for getting this on a better path."

No one would want a master key built that would turn hundreds of millions of locks. Even if that key were in the possession of the person that you trust the most, that key could be stolen. That is what this is about.

It’s clear that it would be a precedent. New York law enforcement is already talking about having 175 phones there. Other counties across the United States are talking about phones they have. And so it is a slippery slope. I don’t fear it; it is one.

Cook: I know people like to frame this argument as privacy versus national security. That is overly simplistic and is not true. This is also about public safety. The smartphone that you carry has more information about you on it than probably any other singular device or any other singular place. Muir: So this is about protecting the safety of the people who carry those iPhones? Cook: That’s exactly right. And by the way, it’s probably just not iPhone. Because if the government could order Apple to create such a piece of software, it could be ordered for anyone else as well. It doesn’t stop here.

Think about this. It is, in our view, the software equivalent of cancer. Is this something that should be created? Technology can do so many things. But there are many things technology should never be allowed to do. And the way you not allow it, is to not create it.

On why iPhones have such deep encryption to begin with:

Cook: Hacking has become increasingly commonplace. It is very difficult to secure data, and the everyday person can’t do it. They look for Apple to help them do it. You need to look no further than the government, which has had some of the worst breaches of all in this case. And so yes, security gets better with every software release we have. Encryption gets more advanced. It has to to stay one step ahead of the bad guys. Muir: So it’s not a mistake that we can’t get into Syed Farook’s iPhone? Cook: We didn’t do it for that reason, David. We did it to protect our customers. But yes, a side effect means that Apple can’t get to it either. Think of it like this: if you put a door in a house, it’s a lot easier to get in that house. It doesn’t matter whether it’s locked or not. Somebody can get in that. And so our simple view is that you encrypt end to end, and you don’t keep a key. And so the people that can see communications are the people on either end of that communication.

On the FBI's specific demands:

Cook: What they want is, they want us to develop a new operating system that takes out the security precautions. Including the precaution that, after 10 tries, if somebody has set "erase all data after 10," they want that to not be in there. And then they want an ability to go through a number of passwords at the speed of a modern computer. Muir: A computer would do that to figure out the code.. Cook: A computer would do that. We believe that is a very dangerous operating system Muir: Because once people know that exists, you say, the cat is out of the bag. Cook: If one of the bad guys knew that that existed, think about the target that is. Everybody would want that system. Because you could get in… It has the potential to get into any iPhone. This is not something that should be created.

On the way forward:

America is strongest when we all come together. There are great people in the FBI and the DoJ and in government — incredible public servants. There’s also some really smart people in technology, and there are some really great people focused on civil liberties. All of these groups need to come together. We’ve recommended a commission; I would be okay with it being called something else or done in a different way. But the key is for all of the key people to come together and really think through these issues. But not just look at one — look at all of them and recognize that at the core of this are some of the founding principles of our country, which we should take a huge pause to trample on.

On the potential for a Supreme Court showdown: