The chief of the military’s new Cyber Command spoke to Congress on Tuesday, explaining that he is establishing 13 teams of programmers and computer experts that could potentially carry out offensive cyberattacks on foreign nations if the U.S. were hit with a major attack on its networks. This marks the first time the Obama administration publicly admitted to developing such a strategy.

“I would like to be clear that this team, this defend-the-nation team, is not a defensive team,” said General Keith Alexander, who runs both the National Security Agency and the new Cyber Command. “This is an offensive team that the Defense Department would use to defend the nation if it were attacked in cyberspace. Thirteen of the teams that we’re creating are for that mission alone.”

General Alexander will add 40 new cyber teams in total, with the other 27 focused on training and surveillance.

The General’s testimony came on the same day that the nation’s top intelligence official James R. Clapper Jr. warned Congress a major cyberattack on the U.S. could “cripple the country’s infrastructure and economy, and suggested that such attacks now pose the most dangerous immediate threat to the United States, even more pressing than an attack by global terrorist networks.”

It’s been a big week for cyberattack discussions. On Monday, national security adviser Thomas E. Donilon “demanded that Chinese authorities investigate such attacks and enter talks about new rules governing behavior in cyberspace,” reports The New York Times. 

One major problem over the years has been how fast different technological advances have become the norm without considering security risks. “In some cases,” Clapper said in his testimony, “the world is applying digital technologies faster than our ability to understand the security implications and mitigate potential risks.”