We're trying, but for the most part we haven't yet developed the type of comprehensive strategy for these types of operations that the PRC has. You should read the US-China Economic and Security Review Commission's report linked from Google's blog entry.
More like the government agencies are all falling over themselves to be the 'one true agency/military branch' that does all of the cyber-defense. I remember a few years ago about the Air Force starting up some sort of Cyber Intelligence branch which was going to be completely separate from any other branch/agency's efforts.
