Cyberwarfare in the United States

Cyberwarfare in the United States is the United States military strategy of proactive cyber defence and the use of cyberwarfare as a platform for attack. The new United States military strategy, makes explicit that a cyberattack is casus belli just as a traditional act of war.
In January 2012, Mike McConnell, the former director of national intelligence at the National Security Agency under President George W. Bush told the Reuters news agency that the U.S. has already launched attacks on the computer networks of other countries. McConnell did not name the country that the U.S. attacked but according to other sources it may have been Iran.
In August 2010, the U.S. for the first time warned publicly about the Chinese military's use of civilian computer experts in clandestine cyber attacks aimed at American companies and government agencies. The Pentagon also pointed to an alleged China-based computer spying network dubbed GhostNet that was revealed in a research report last year. The Pentagon stated:
"The People's Liberation Army is using "information warfare units" to develop viruses to attack enemy computer systems and networks, and those units include civilian computer professionals. Commander Bob Mehal, will monitor the PLA's buildup of its cyberwarfare capabilities and will continue to develop capabilities to counter any potential threat."
The United States Department of Defense sees the use of computers and the Internet to conduct warfare in cyberspace as a threat to national security.The United States Joint Forces Command describes some of its attributes:
Cyberspace technology is emerging as an "instrument of power" in societies, and is becoming more available to a country's opponents, who may use it to attack, degrade, and disrupt communications and the flow of information. With low barriers to entry, coupled with the anonymous nature of activities in cyberspace, the list of potential adversaries is broad. Furthermore, the globe-spanning range of cyberspace and its disregard for national borders will challenge legal systems and complicate a nation's ability to deter threats and respond to contingencies.
In February 2010, the United States Joint Forces Command released a study which included a summary of the threats posed by the internet:
With very little investment, and cloaked in a veil of anonymity, our adversaries will inevitably attempt to harm our national interests. Cyberspace will become a main front in both irregular and traditional conflicts. Enemies in cyberspace will include both states and non-states and will range from the unsophisticated amateur to highly trained professional hackers. Through cyberspace, enemies will target industry, academia, government, as well as the military in the air, land, maritime, and space domains. In much the same way that airpower transformed the battlefield of World War II, cyberspace has fractured the physical barriers that shield a nation from attacks on its commerce and communication. Indeed, adversaries have already taken advantage of computer networks and the power of information technology not only to plan and execute savage acts of terrorism, but also to influence directly the perceptions and will of the U.S. Government and the American population.