An empire of carnage unleashed from an arsenal of weapons high above the Las Vegas Strip left what looked like a battlefield on American soil.

But in the immediate hours after the worst mass shooting in modern American history, authorities said the brutal bloodshed was not considered an act of terrorism. Instead, Clark County Nev. Sheriff Joe Lombardo said the individual “resides here locally. .… We don’t know what his belief system was at this time.”

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Along with the echoes of mass shootings in American life, the echoes of whether law enforcement should call mass murder “terrorism” continued, as concert-goers carried the dead from a dark field in Nevada.

The killings across from the Mandalay Bay Hotel may meet the state of Nevada’s definition of terror, but may not meet the more important federal standard.

According to a 2003 addition to Nevada state code, an “act of terrorism” means any act that involves the use or attempted use of sabotage, coercion or violence intended to:

(a) Cause great bodily harm or death to the general population; or

(b) Cause substantial destruction, contamination or impairment…

Motive is not mentioned in the Nevada terror definition.

But motive is key in the federal definition. And body count is largely a secondary concern if an act is defined as terrorism by federal officials.

“In reality, a state does not have jurisdiction over a deemed act of terrorism – the federal law supersedes all,” said Dr. Scott J. White, a former intelligence officer now serving as an associate professor at the George Washington University.

“If you call an act ‘terror,’ that opens the investigation to the FBI, the Department of Homeland Security, and all our intelligence assets that may not be necessary in a criminal case with 59 counts of homicide.”

In some cases, a terrorism investigation opens the resources of the nation’s intelligence community to local officials. Intelligence gathering with a global reach would not be necessary for a domestic lone wolf case – the leading theory of the Las Vegas shooting investigation.

Federal law also defines terrorism as violence with a specific societal purpose:

“The unlawful use of force and violence against persons or property to intimidate or coerce a government, the civilian population, or any segment thereof, in furtherance of political or social objectives.”

Bottom line – all acts of terrorism are investigated by the FBI.

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It is not possible for local officials in Nevada to investigate the Las Vegas shootings as a terror case on their own.

“You can be terrorized, and there can be terror on the Las Vegas Strip, but it’s not necessarily terrorism under the law,” White said. “That definition may not matter to a family member, but it matters to how law enforcement responds, and what resources are deployed.”