Edward Snowden, the man responsible for leaking thousands of secret documents to the media, has resurfaced from his asylum in Moscow on the same day that an independent review panel recommends a US surveillance programme be scrapped.

The former US security contractor participated in an online question an answer session on Thursday. He used the web forum to promote a new report by a federal independent watchdog, the Privacy and Civil Liberties Oversight Board (PCLOB), which concluded that the government's surveillance programme is both ineffective and illegal.

"Not all spying is bad. The biggest problem we face right now is the new technique of indiscriminate mass surveillance, where governments are seizing billions and billions and billions of innocents’ communication every single day," responded Snowden to a question submitted to him through Twitter.

Under section 215 of the Patriot Act, the National Security Agency (NSA) collects billions of records daily then stores the private information of individuals for years.

"The fact that these records are gathered without the government having any reasonable suspicion or probable cause justifying the seizure of data is so divorced from the domain of reason as to be incapable of ever being made lawful at all," Snowden wrote. "We can correct the laws, restrain the overreach of agencies, and hold the senior officials responsible for abusive programs to account."

Comments from the former spy agency contractor have reignited the media debate on surveillance, causing headaches for US President Barack Obama, who has been trying to put the issue onto the backburner.

"If any individual who objects to government policy can take it into their own hands to publicly disclose classified information, then we will not be able to keep our people safe, or conduct foreign policy," Obama said on January 17. "Moreover, the sensational way in which these disclosures have come out has often shed more heat than light, while revealing methods to our adversaries that could impact our operations in ways that we may not fully understand for years to come."

'Mission's already accomplished'

Shortly after a federal judge ruled on December 2013 that bulk collection of Americans' telephone records likely violated the constitution, Snowden appeared emboldened.

There is simply no justification for continuing an unconstitutional policy with a 0% success rate. Edward Snowden

"I already won," Snowden told the Washington Post in a December interview. "I didn’t want to change society. I wanted to give society a chance to determine if it should change itself."

Since then, editorial boards of major newspapers have published op-eds calling for leniency in Snowden's case.

Then late Thursday, the PCLOB released its 3-2 decision that collecting metadata like phone calls and other private records was constitutionally unsound. During the past seven years, the board found no attacks thwarted through the NSA programme.

"The majority of the board takes a view that the 215 programme is not authorised by statute, that it raises serious constitutional and privacy concerns and has not demonstrated sufficient effectiveness to continue in operation on a permanent basis," David Medine, chairman of the board, said on Thursday.

During Thursday's web forum, Snowden wrote: "When even the federal government says the NSA violated the constitution at least 120 million times under a single programme, but failed to discover even a single "plot," it’s time to end "bulk collection," which is a euphemism for mass surveillance. There is simply no justification for continuing an unconstitutional policy with a 0% success rate."

The board, which included two dissents, has no judicial teeth, so it's unclear what affect - if any - the decision will have on surveillance policy. The board met with Obama to discuss its findings ahead of the US President's January 17 speech about the NSA.

But advocates say that Snowden, and the privacy watchdog group, will continue to drive the privacy issue in Washington.

"I think the Obama administration now has a dilemma," Greg Nojeim, senior counsel for Center for Democracy & Technology, told Al Jazeera in a phone interview.

"The DOJ [Justice Department] argues the programme is lawful. The board said the programme is unlawful. One federal court found the programme was unconstitutional. Another federal court found that it is constitutional. That’s the kind of conflict that results in changes. Underlying that is the fact that it hasn’t thwarted a single violent act. This programme's days are numbered," Nojeim said.

"Snowden’s disclosures have prompted the conversation that we are now having about surveillance."

Surveillance as usual

Despite the panel's findings and Snowden’s partial vindication in the media, Obama has chosen to back the much-talked-about NSA programme - not scrap it.

"We simply disagree with the board's analysis on the legality of the programme," White House spokesman Jay Carney said on Thursday. "The administration believes that the programme is lawful. As the president has said, however, he believes we can and should make changes in the programme that will give the American people greater confidence in it."

Snowden's actions have drawn praise and aniomsity [Reuters]

Obama has proposed modest changes to how the NSA carries out surveillance on a day-to-day basis.

For example, he proposed moving billions upon billions of records the government currently warehouses to a third party, in order to ensure that surveillance is more targeted.

Supporters of NSA surveillance say that President Obama's real aim isn't to push any reform.

"The main point that the president made was that intelligence and this programme is legal, it’s been useful, and it will continue," Eugene Poteat, former CIA scientific intelligence officer and president of the Association of Former Intelligence Officers, told Al Jazeera. The president is trying to placate privacy activists, the former spy said, through a series of cosmetic changes such as "where the information is stored".

Under the proposed changes the government will still be able to retrieve personel data "when it's needed", Poteat said.

The US public, for its part, is sceptical about proposed changes to the spy programme. The majority now oppose it. An overwhelming 73 percent of Americans said they thought Obama's NSA tweeks would make no difference to the status quo, according to a new Pew Research Center/USA Today poll.

'No way home'

As the debate between privacy versus security rages on the internet and in the halls of power, many former intelligence officers believe Snowden has helped construct a false dichotomy.

"What Snowden released has helped the terrorists to change their tactics and make it more difficult to find them," said Poteat, who labels Snowden a traitor. "I hate to think of the consequences if these programs are not continued."

Eric Holder, the US Attorney General, seems to share that view.

On Thursday, Holder said that granting Snowden clemency was out of the question. "He broke the law, he caused harm to our national security - I think he has to be held accountable for his actions."

But for Snowden's part, he just wants to go home.

"Returning to the US, I think, is the best resolution for the government, the public, and myself, but it’s unfortunately not possible in the face of current whistleblower protection laws, which through a failure in law did not cover national security contractors like myself."