While the United States has a first-rate cyberoffense capacity, according to Richard A. Clarke, it lacks a credible defense systems, combined with the country’s heavy reliance on technology, making it highly susceptible to a devastating cyberattack.  The United States is currently far more vulnerable to cyberwar than Russia or China, he says.

http://www.nytimes.com/2010/04/27/books/27book.html