In the search for answers in the wake of the shootings in Aurora, Colo., authorities have made one curious conclusion about the suspect, James Holmes. The FBI has made clear that Mr. Holmes has no ties to terrorism. This is flat wrong — he is a terrorist. And this label matters. According to the police, Mr. Holmes — armed with an assault rifle and other guns, and ensconced in battle armor — indiscriminately and emotionlessly shot at moviegoers, some of whom were children, and some of whom were trying to escape. The rampage also appears to have been premeditated. Mr. Holmes recently bought thousands of rounds of ammunition and, on the night of the movie premiere, authorities say, he calmly purchased a ticket and returned to his car to prepare himself before reentering the theater to disorient and then shoot at the large crowd. He now faces charges of killing 12, including a 6 year-old girl, and injuring dozens more. That mass shooting inflicted deep psychological wounds on countless others. For that reason alone, the crime Mr. Holmes is accused of — the cold, calculated shooting of innocents in a movie theater — qualifies as terrorism and its perpetrator as a terrorist. As Adam Gopnik notes in The New Yorker, "we don't know, and perhaps never will, what exactly 'made him' do what he did; but we know how he did it." The "why" may explain and offer context, but the "how" is enough for the incident to fall into the category of terrorism. To suggest otherwise and insist that acts of terrorism must be premised on an established ideology or discernible beliefs would be to place subjective motivation above objective action. It would be to posit, in effect, that the "terrorism" definition applies without question to those who claim some allegiance to radical Islam, regardless of their psychological condition, whereas all others get the benefit of the doubt. This double-standard is unfair to Muslims and lets everyone else off the hook, to our own peril. Accordingly, there are advantages to defining terrorism as the premeditated, random murder of innocent people that causes physical and psychological harm on a community, without regard to whether the perpetrator attempted to further a possible message. A terrorist, through his or her conduct, severs connections with orderly society. Mr. Holmes, by his conduct, is no longer worthy of any identity other than that of a terrorist, much in the same way that individuals who pervert Islam to justify terrorism deny themselves any valid claim to be Muslims. To call Mr. Holmes a terrorist would be to acknowledge the social significance of his acts, deny him any political or personal cover for those acts, and to signal the extent of the public's condemnation. To be sure, Mr. Holmes; Jared Lee Loughner, who is charged in the shooting that seriously wounded Rep. Gabrielle Giffords and killed six others; and Virginia Tech shooterSeung-Hui Cho were all loners and thus may have felt marginalized as is. The "terrorist" label would, however, impose an additional social cost to their actions and may undermine any permanent legacy that such mass murderers are ostensibly seeking. In failing to immediately and universally frame Friday's incident as terrorism, we failed to properly conceptualize what occurred, failed to hand down a swift and damning social sentence on the perpetrator, and failed to further disincentivize similar incidents. The terrorism label also has national security implications. Last week, a government inquiry into the 2009 Fort Hood shootings revealed that officials were reluctant to investigate Major Nidal Hasan because of concerns that they would be perceived to be profiling Muslims. But if we weren't so reluctant to label as terrorism horrific acts like the Colorado theater shootings, we might not be so concerned about appearing bigoted against Muslims. If our definition of terrorism centered on conduct, not ideology, our security officials would be freed to focus on scrutinizing individualized behavior, such as emailing known terrorists, flying long distances one-way without checked bags, or amassing huge stockpiles of ammunition. In doing so, our defense against domestic shootings may be heightened and such incidents might have less of a chance recurring. And as the Fort Hood report suggests, such a shift in how we think about terrorism might have helped us prevent Mr. Hasan from engaging in the mass shooting in the first place. As we continue to mourn and debate the propriety of stronger gun control laws, among other responses to these killings, let us agree upon two certainties. What took place on Friday is a tragedy. It is also terrorism. Dawinder S. Sidhu, a Maryland native, is an assistant professor at the University of New Mexico School of Law. His email is email@example.com.