When millions took to the streets of Egypt last week to protest the Mubarak regime and call for democratic reform, the Egyptian government responded by cutting off Internet access and people's ability to communicate with one another and the outside world.

Such drastic action is a new way for governments to smother popular movements worldwide... just as more and more people are turning to Twitter, Facebook and Youtube and using cell phones to mobilize for social chance and speak out against authoritarian regimes.

What's very worrying is that Congress is weighing legislation in the U.S. that could give our president the authority to flip the "kill switch" on the Internet and plunge the nation into digital darkness.

Sens. Joe Lieberman (I-Conn.), Susan Collins (R-Maine) and Thomas Carper (D-Dela.) introduced legislation in the last Congress that would give the Executive Branch far-reaching authority to cut off "critical infrastructure" in times of crisis.

The "Protect Cyberspace as a National Asset Act" wasn't passed in 2010. But, according to a recent report in Wired, Sens. Collins and Lieberman plan to reintroduce the bill in the new Congress. The bill as written offers a vague definition of what constitutes an emergency, and fails to create effective checks and balances.

Confronted by overwhelmingly negative public response, sparked in part by theWired story, the senators have gone on the defensive about the legislation. They issued a statement on Tuesday offering assurances that they do not seek to create a "kill switch" over the Internet.

Whatever the intentions, the reportedly broad, ambiguous language of the bill and its lack of safeguards for individual freedoms are deeply troubling. We need to be certain that no bill gives government the authority to cut off Internet access. Such power, in the hands of the top executive, poses a drastic threat to our First Amendment right to free speech and assembly.

The events in Egypt show the power of the Internet in fostering free speech and reform. Both progressive and conservative activists in the U.S. have relied on the organizing capacity of the Web and social networks to build popular movements as well.

We must guard against any effort to curtail our access to the open Internet. Take action here and stay tuned as this story continues to develop.