The Obama administration brought Facebook and Twitter to politics. And now it’s giving back, as staffers leave the White House and take key jobs at Silicon Valley firms.

In the past year, Facebook hired Marne Levine, a former White House economic official, and is reportedly courting former West Wing spokesman Robert Gibbs. Google’s philanthropy arm snagged Jared Cohen, the State Department’s social media guru. Twitter hired former White House and State Department staffer Katie Stanton.

The revolving door between the federal government and U.S. tech companies isn’t new. But the hires come as popular Internet applications from Google, Facebook and Apple attract special attention from lawmakers and regulators concerned about issues of privacy, competition, pricing and other aspects of the rapidly changing online economy.

Facebook has been probed by the Federal Trade Commission for changing its privacy policies and catching users by surprise. Lawmakers have criticized the company for its muted response to authoritarian governments who want to clamp down on Internet communications.

Google is being investigated by the Federal Communications Commission for snarfing up consumer Wi-Fi Internet data.

Apple is also being probed for the way it uses its control over the iTunes store to take cuts of revenue from applications sold there.

“These companies are at the crosshairs of privacy and policy issues and they see people in the White House and federal government as protectors of their plans to expand into new markets,” said Jeffrey Chester, an online privacy advocate and executive director of the Center for Digital Democracy. “These are uber influence-makers they are hiring.”

Facebook declined to comment on a report by the New York Times that it is trying to hire Gibbs for a senior communications position. Gibbs, who left the White House in February, did not respond to an e-mail request for an interview. (Washington Post Co. Chairman Donald Graham sits on the board of Facebook).

Experts said that if Gibbs joined a private firm such as Facebook and registered as a lobbyist, he would not be allowed to contact staffers at the White House about business issues during Obama’s tenure.

But Gibbs would be valuable not only for his contacts but also for his deep knowledge of Obama’s agenda. He is among a small number of people who can articulate the president’s mission on dozens of issues off the cuff, observers say.

That skill is useful for companies trying to navigate federal government policy and global strategies. And the hire would be a public relations coup, underscoring the company’s influence to other governments and competitors.

“The executive branch [lobbying] rules are very good, but we also have to recognize the reality that a lot of people who leave the administration go to work for organizations that have interests in government decisions,” said Fred Wertheimer, president of government reform group Democracy 21.

Those interests have intensified in recent months, and the firms want a stronger voice before government officials, experts say.

The White House said earlier this month that it supports the creation of online privacy legislation. Companies worry that new laws could go too far and hamper the ability of firms such as Apple, Google, Foursquare and Zynga to collect information about users and share that data with advertisers. In the past year, the FCC was at the center of a lobbying war over rules that prevent cable and phone companies from blocking Internet traffic or favoring particular Web firms.

In response, Apple recently hired Washington consultants and expanded its full-time lobbying staff. Twitter hired a former Capitol Hill staffer as its face in Washington, too.

Google’s green energy initiative hired consultant Colin Crowell, who is both a former senior adviser to the FCC’s chairman and a former aide to Rep. Edward J. Markey (D-Mass.).

The new relationships between Internet companies and the federal government follow those of phone and computer giants and government officials. Ahead of the regulatory review of its merger with T-Mobile, AT&T has as its lobbying leader James Cicconi, a former staffer for George W. Bush. Cicconi has a long track record of regulatory success at the FCC and approval of several mergers for AT&T. Bill Clinton spokesman Mike McCurry heads Arts & Labs, a group that has lobbied against Internet access rules known as net neutrality, on behalf of AT&T, Verizon and cable companies.

Now, Internet companies find that they need the government more.

“The tech industry has grown up and they recognize that talented people and skills are transferable in the tech and policy world such as collaboration and openness with social media,” said Jim Hock, president of tech public relations firm 463 Communications.