That could result in a "breathtaking power grab" by the White House, added Harris, who said the provision appears to assume that the government is better than the private sector is at identifying security threats and responding to them during emergencies.

Gartner Inc. analyst John Pescatore agreed that as currently written, the cybersecurity bill is a "major overreach." Some aspects of the bill would be welcome if they were focused specifically on improving , he said. NIST, for instance, should be playing a more active rule in developing government security standards, and the shouldn't be in charge of the federal security agenda, according to Pescatore.

"However, trying to have the government enforce cybersecurity standards on private industry would be a major step in the wrong direction," he said. "It would slow down the reaction time to new threats, not speed it up."

The Rockefeller-Snowe bill is loosely modeled on a set of issued last December by a commission that was set up by the Washington-based Center for Strategic and International Studies (CSIS) in late 2007, in an attempt to provide some external guidance to the next president.

James Lewis, director of the technology and public policy program at the CSIS, said that he thinks the proposed legislation does a good job overall of addressing several key security-related issues. "I love the bill," Lewis said. "It is really bold." But the provision granting the president new authority over private-sector networks will "trigger some debate," he conceded. "That is clearly going to be a problem for some people."