The U.S. Cyber Command's top intelligence officer accused China on Thursday of persistent efforts to pierce Pentagon computer networks and said a proposal was moving forward to boost the cyber command in the U.S. military hierarchy.
 
The overall sophistication and danger of cyber threats is increasing at an accelerating rate, not a linear rate. So the potential for these things to do destructive damage is very high. Army General Keith Alexander, who simultaneously heads Cyber Command and the National Security Agency, told a forum in July that unspecified foreign countries, hackers and criminal gangs contributed to a 17-fold jump in cyber attacks on U.S. infrastructure from 2009 to 2011.

Source: Huffington Post, http://www.huffingtonpost.com/2012/09/27/samuel-cox-us-cyber-command-china_n_1921465.html?utm_hp_ref=technology