Glenn Greenwald in The Intercept:
Chelsea Manning was revealed as the whistleblower responsible for one of the most important journalistic archives in history, her heroism has been manifest. She was the classic leaker of conscience, someone who went at the age of 20 to fight in the Iraq War believing it was noble, only to discover the dark reality not only of that war but of the U.S. government’s actions in the world generally: war crimes, indiscriminate slaughter, complicity with high-level official corruption, and systematic deceit of the public.
In the face of those discoveries, she knowingly risked her own liberty to disclose documents to the world that would reveal the truth, with no expectation of benefit to herself. As someone who has spent years touting the nobility of her actions, my defenses of her always early on centered on the vital nature of the material she revealed and the right of the public to know about it.
It is genuinely hard to overstate the significance of those revelations: Aside from exposing some of the most visceral footage of indiscriminate slaughter by the U.S. military seen in decades, the leaks were credited — even by harsh WikiLeaks skeptics such as New York Times Executive Editor Bill Keller — with helping to spark the Arab Spring. Even more significantly, revelations about how the U.S. military executed Iraqi civilians, then called in a bombing raid to cover up what they did, prevented the Iraqi government from granting the Obama administration the troop immunity it was seeking in order to extend the war in Iraq.
More here.