Former Army Pvt. Chelsea Manning says she has accepted responsibility for leaking more than 700,000 documents to WikiLeaks – but was never concerned that her actions threatened national security.

“Anything I’ve done, it’s me. There’s no one else,” she told “Nightline” when asked if she felt she owed the American public an apology. “No one told me to do this. Nobody directed me to do this. This is me. It’s on me.”

Manning, 29, a transgender woman formerly known as Bradley, was released last month from the US Disciplinary Barracks at Fort Leavenworth after serving seven years of her 35-year sentence in the largest leak in US intelligence history.

Just before leaving the White House in January, President Obama granted her clemency, saying time served was punishment enough.

Manning wore a floor-length tan dress and a crew-neck sweater for her interview, which will air early next week. In a preview Friday on “Good Morning America,” she started crying when Juju Chang mentioned Obama’s name.

“I’ve been given a chance,” she said, adding that she would want to thank the former president. “That’s all I asked for was a chance. That’s it, and now this is my chance.”

Manning was a 22-year-old low-level analyst when she leaked information about battlefield reports from Iraq and Afghanistan, evidence of civilian deaths in the countries, profiles of Guantanamo detainees and US diplomatic correspondence.

“We’re getting all this information from all these different sources and it’s just death, destruction, mayhem,” she said when asked what compelled her to risk her career and break the law.

“We’re filtering it all through facts, statistics, reports, dates, times, locations, and eventually, you just stop,” she continued. “I stopped seeing just statistics and information, and I started seeing people.”

She said she didn’t think her leaks would threaten national security – just spark public debate.

“I work with this information every day,” Manning said. “I’m the subject matter expert for this stuff. You know, we’re the ones who work with it the most. We’re the most familiar with it. It’s not, you know, it’s not a general who writes this stuff.”

When asked why she didn’t take her concerns up the chain of command, Manning said, “The channels are there, but they don’t work.”

Manning, who pleaded guilty to some charges, was acquitted of the most serious charge — aiding the enemy. Days after being sentenced, she came out as transgender on Aug. 22, 2013.

The Army would not provide her with any treatment for her gender dysphoria, which she claimed led to her mounting distress.

In September 2014, her ACLU lawyer filed a lawsuit on her behalf.

Manning became “the first military prisoner to receive health care related to gender transition and was part of a shift in practice that lead to the elimination of the ban on open trans service in the military,” attorney Chase Strangio said.

Manning said it was important for her to fight for hormone treatment.

“[It] keeps me from feeling like I’m in the wrong body,” she said. “I used to get these horrible feeling like I just wanted to rip my body apart and I don’t want to have to go through that experience again. It’s really, really awful.”

After her May 17 release, Manning has been documenting her life on her Instagram and Twitter accounts.

When asked what she thought about the military today, she said, “I have nothing but utmost respect for the military.

“The military is diverse, and large, and it’s public, it serves a public function, it serves a public duty,” she said. “And the people who are in the military work very hard, often for not much money, to make their country better and to protect their country. I have nothing but respect for that. And that’s why I signed up.”