Cyberwarfare is the use of computer technology to disrupt the activities of a state or organization, especially the deliberate attacking of information systems for strategic or military purposes. As a major developed economy, the United States is highly dependent on the Internet and therefore greatly exposed to cyber attacks. At the same time, the United States has substantial capabilities in both defense and offensive power projection thanks to comparatively advanced technology and a large military budget. Cyberwarfare presents a growing threat to physical systems and infrastructures that are linked to the internet. Malicious hacking from domestic or foreign enemies remains a constant threat to the United States. In response to these growing threats, the United States has developed significant cyber capabilities.

The United States Department of Defense recognizes the use of computers and the Internet to conduct warfare in cyberspace as a threat to national security, but also as a platform for attack.

The United States Cyber Command centralizes command of cyberspace operations, organizes existing cyber resources and synchronizes defense of U.S. military networks. It is an armed forces Unified Combatant Command. A 2021 report by the International Institute for Strategic Studies placed the United States as the world's foremost cyber superpower, taking into account its cyber offense, defense, and intelligence capabilities.

Cyberwarfare is the use of cyber attacks against an enemy state, causing comparable harm to actual warfare and/or disrupting vital computer systems. Some intended outcomes could be espionage, sabotage, propaganda, manipulation or economic warfare.

There is significant debate among experts regarding the definition of cyberwarfare, and even if such a thing exists. One view is that the term is a misnomer since no cyber attacks to date could be described as a war. An alternative view is that it is a suitable label for cyber attacks which cause physical damage to people and objects in the real world.

Many countries, including the United States, United Kingdom, Russia, China, Israel, Iran, and North Korea, have active cyber capabilities for offensive and defensive operations. As states explore the use of cyber operations and combine capabilities, the likelihood of physical confrontation and violence playing out as a result of, or part of, a cyber operation is increased. However, meeting the scale and protracted nature of war is unlikely, thus ambiguity remains.

In September 2023, Department of Defense (DoD) published its latest Cyber Strategy, building upon the previous DoD Strategy for Operating in Cyberspace published in April 2015 and July 2011. The DoD Cyber strategy focuses on building capabilities to protect, secure, and defend its own DoD networks, systems and information; defend the nation against cyber attacks; and support contingency plans. This includes being prepared to operate and continue to carry out missions in environments impacted by cyber attacks.

The DoD outlines three cyber missions: