Privacy-minded organizations scrambled Wednesday to marshal opposition to a bill introduced in the House of Representatives on Tuesday that would extend and expand US government surveillance powers.

Former National Security Agency contractor Edward Snowden joined the American Civil Liberties Union in an ask me anything, or AMA, discussion on Reddit to rally opponents to an amendment to the newest effort at updating 1978's Foreign Intelligence Surveillance Act. The act lets the NSA snoop on foreign targets without a search warrant, but the ACLU, the Electronic Frontier Foundation and the Open Technology Institute say it goes too far by making it easier to sweep up information on US citizens as well.

"This bill would make current law measurably worse and open up new avenues for government overreach," ACLU lawyer Neema Singh said. "Instead of preventing the government from warrantlessly searching [FISA-related] databases for information about American citizens and residents, the bill could be interpreted as codifying this illegal practice."

It appeared the bill's opponents got their way at least for a time on Wednesday, as a result of different Republican Party priorities, according to The Washington Post.

James Martin/CNET

The fight against the surveillance bill embodies digital-era challenges for society. Data is more abundant than ever, but it's also more personal than ever and easier to search and process. The trick is to give intelligence agencies the power to spot terrorist plots without large-scale prying into everyone's Facebook posts, emails, text messages, photos and videos.

"If you get swept up in the dragnet and your comms somehow end up as results on an analyst's query, at that point, the NSA and FBI start considering your private records under a new legal status, calling them 'incidentally collected,'" Snowden said. "These 'incidentally collected' communications of Americans can then be kept and searched at any time, without a warrant."

A report accompanying the bill, though, says it "strikes the appropriate balance between privacy and national security." It "makes critical improvements to privacy and civil liberties while resulting in no negative operational impact to United States' surveillance authorities," the House Intelligence Committee report said.

In Congress, the bill's opponents have some support, including libertarian-leaning Sen. Rand Paul, a Republican from Kentucky, who said on Twitter, "I will actively oppose and filibuster any long-term extension of warrantless searches of American citizens," and Sen. Ron Wyden, an Oregon Democrat, who responded, "I'll be right there with you."

I will actively oppose and filibuster any long term extension of warrantless searches of American citizens — Senator Rand Paul (@RandPaul) December 20, 2017

The FISA surveillance provision expires at the end of the year, and Congress has been working for months on how to extend it. If the four-year extension in the latest bill fails, short-term extensions also are possible.

Snowden rose to prominence after leaking NSA files to media outlets, which published a series of stories about the US government's surveillance practices. He's living in Russia under temporary asylum and is wanted by the US government under the Espionage Act.

He's been a polarizing figure. Snowden has been called a traitor, and the House Intelligence Committee said in a 2016 report, "Snowden caused tremendous damage to national security."

Some are willing to see him in a different light. One Redditor asked Snowden if he'd run for president if he were pardoned with full immunity.

"I'm an engineer, not a politician, but of course I'd be glad to come home," Snowden responded. "I'd fight to fix the place, not to tear it down."

CNET's Terry Collins contributed to this report.

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