During an exclusive interview with "This Week," Facebook CEO and FWD.us founder Mark Zuckerberg criticized the current U.S. immigration system and framed comprehensive reform as a major civil rights issue.

"When you meet these children who are really talented, and they've grown up in America and they really don't know any other country besides that, but they don't have the opportunities that … we all enjoy, it's really heartbreaking - right? That seems like it's one of the biggest civil rights issues of our time," Zuckerberg said.

Zuckerberg - speaking to ABC News' David Wright this week from Mountain View, Calif. - pushed back against those who argue the millions of undocumented immigrants estimated to be in the United States are here illegally and have no right to citizenship.

"There are a lot of misconceptions about that … a lot of them came here because they just want to work. They want to help out their families and they want to contribute," he said.

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The 29-year-old billionaire - who co-founded the immigration reform advocacy group FWD.us this spring - outlined the economic importance of reform.

"The future of our economy is a knowledge economy. And that means that getting the most talented people into this country is the most important thing that we can do to make sure that the companies of tomorrow are founded here," Zuckerberg said.

For a "hackathon" Wednesday, Zuckerberg brought together a group of undocumented immigrants, the youngest of whom are known as "dreamers" because of the DREAM Act, a proposed immigration reform that would give legal residency to young immigrants who meet certain educational or service requirements.

"One of the things that the 'dreamers' here today show is that even if, you know, you're a child of someone who came here who wouldn't be considered one of the higher-skilled workers … you can be one of the entrepreneurs of tomorrow," Zuckerberg said. "That's the American dream."

Even though an immigration deal in Congress seems elusive, Zuckerberg is staying optimistic about the future.

"I'm fundamentally an optimistic person, as an entrepreneur," he said. "The vast majority of Americans want this to happen."

Zuckerberg also addressed the government's recently revealed intelligence surveillance programs.

"These things are always a balance in terms of doing the right things and also being clear and telling people about what you're doing," Zuckerberg said of the NSA's transparency on its surveillance activities.

"I think the government really blew it on this one," he said. "I honestly think that they're continuing to blow it in some ways, and I hope that they become more transparent in that part of it."

Asked about the botched rollout of healthcare.gov, Zuckerberg seemed to express sympathy for the Obama administration, which has been grappling with the practical and political consequences of the problem-plagued website since it launched last month.

"You know, sometimes stuff doesn't work when you want it to. We've certainly had plenty of mistakes and things that haven't worked the way that we want to," Zuckerberg said of Facebook's own challenges rolling out features on the social networking site.

"The right thing here is just to keep on focusing on building the service that you think is right in the long term," he said.

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