We've all heard of Google bombing; the US Government may be taking the expression rather literally. Planning is now underway across the government for the proper way to respond to a cyber attack, and options on the table include launching a cyber counterattack or even
bombing the attack's source. The article makes clear that no settled plan is in place, and quotes one spokesman as saying "the preferred route would be warning the source to shut down the attack before a military response." That's assuming the source could be found. From the article:
"If the United States found itself under a major cyberattack aimed at undermining the nations critical information infrastructure, the Department of Defense is prepared, based on the authority of the president, to launch a cyber counterattack or an actual bombing of an attack source."