Perfect Citizen will focus on older control systems not originally designed to be connected to the Internet and now vulnerable to cyber attacks. Military officials defended the program, claiming it is long overdue and that any invasion of privacy is roughly comparable to a traffic camera. Participation will be voluntary, though there will be government incentives to participate, particularly for companies already doing business with federal agencies.

But the secrecy surrounding the program has raised doubts among civil liberties advocates including Jim Harper, director of information policy studies at the Cato Institute.

“If there is to be a federal government role in securing the Internet from cyberattacks, there is no good reason why its main components should not be publicly known and openly debated,” Harper wrote Thursday in a blog post. “Benign intentions do not control future results, and governmental surveillance of the Internet for ‘cybersecurity’ purposes may warp over time to surveillance for ideological and political purposes.”