n. A hacker who attempts to infiltrate or disable the computer systems of people or organizations that are perceived to be hostile to the hacker's country.
2001
In an advisory posted on an FBI Web site, officials warned Internet service providers worldwide to be on the lookout for "self-described 'patriot' hackers [targeting] those perceived to be responsible for the terrorist attacks" of the Pentagon and World Trade Center.
1996 (earliest)
Although today's term has been much in evidence lately in light of the recent atrocities in New York and Washington, the phrase has been around for a few years. In the earliest citation however, the "hacker" was a soldier who gave computer passwords to a Chinese citizen. His lawyer and family claimed that he was only trying to show his superiors there were problems with an "expensive, supposedly impenetrable system."