Bradley Manning, the alleged source of WikiLeaks' dossiers on Iraq and Afghanistan, is not a traitor - and big firms must take a stand to protect whistle-blowers from US government demands to spy on their data, according to Daniel Ellsberg, the former CIA man who leaked the Pentagon Papers.
Ellsberg, who last year signed an open letter supporting WikiLeaks, said companies such as Google, Facebook and Twitter need to stand firm in the face of excessive requests by government for access to personal data.
"You are facing a challenge at this moment of profound implications for our democracy," Ellsberg told Silicon Valley executives in Santa Clara, California, on Wednesday night.
Ellsberg was part of a panel discussing the reaction of corporations such as Amazon, eBay, Visa and Mastercard to US government pressure aimed at shutting down the whistle-blowing site.
As more and more information about our lives - in the form of Twitter posts, Facebook status updates, tagged pictures and blog entries, is posted online - the companies hosting it must take the lead in pushing back at government requests for greater access, says Ellsberg.
"Facebook, Google, Twitter: Put them all together. If they're all working together, their ability to manipulate us, to know [about us], this is absolutely antithetical to democracy," Ellsberg said.
"People in this audience have the ability to decide that they are ready to take a risk in their lives to fight to preserve democracy in this country and to preserve us from total transparency to our executive branch," he added.
Micro-blogging site Twitter became the centre of controversy after it was revealed that US authorities had in December requested access to the accounts of a number of subscribers with links to WikiLeaks. The request was only made public after Twitter fought to lift a gagging order attached to the original subpoena, which prevented it from being reported - even to the individuals concerned.
Facebook has refused to say whether it has received similar requests, but spokesman Andrew Noyes said: "We are required to regularly push back against over-broad requests for user records. ... In most cases we are able to convince the party issuing legal process to withdraw the overbroad request, but if they do not we fight the matter in court - and have a history of success in those cases."
Google recently came under fire after telling UK police to obtain a court order if they wanted to get their hands on the unedited original version of a Street View image the police wanted in order to investigate the theft of a family's caravan. One MP from the ruling Conservative Party suggested that the search giant should hand over information to the authorities on demand.
Online rights group the Electronic Frontier Foundation recently published details of the procedures set down by a number of leading social media websites governing requests for information on subscribers.
During the discussion on Wednesday, Ellsberg noted similarities between his case and that of US Army private Bradley Manning, the soldier arrested over allegations that he leaked information to Wikileaks. According to reports, Manning has been tortured while in custody.
Ellsberg said he felt a "very great affinity with Bradley Manning."
"If Manning were to be tried, he'd have to be tried for treason," said Ellsberg. "And he is no more traitor than I was."