James Paddock meticulously planned his Las Vegas attack, spending years stockpiling firearms and ammunition and scouting a number of potential targets before settling on the "Route 91 music festival."

On September 28, Paddock checked into a hotel room on the 32nd floor of the Mandalay Bay Resort and Casino.  He had specifically requested a room with a view of the plaza where the concert would be held.  Paddock then used the next few days to haul firearms and ammunition up to his hotel room.

Paddock's careful planning of his attack was not unique.  Mass shooters can spend months, even years, planning their attacks.  In other ways, however, Paddock's attack on the Route 91 music festival represents a terrifying escalation.  Paddock's use of a prepared position and fully automatic weapons are new developments that will not go unnoticed by future mass shooters.

When the Connecticut State Police searched the home of Sandy Hook murderer Adam Lanza, they discovered a 4x7 foot spreadsheet detailing past mass shootings and attempted mass shootings.  Lanza studied these atrocities in order to plan his own attack.

Lanza isn't unique; in the words of Peter Bergen, "[i]n the United States, school shooters study other school shooters, in particular Columbine. This is true of terrorists as well. They study tactics that have worked before."

Mass shooters don't just study what "works"; they also study what draws the most media attention.

According to a recent study by Adam Lankford and Eric Madfis, many mass shooters are motivated by fame.  From observing media coverage of past attacks, mass shooters concluded that the more people they killed or injured, the more media attention they received.

This makes the Vegas attack especially worrisome.  Potential mass shooters might see the large number of victims, along with the extensive media coverage, and emulate Paddock.

During the First World War, it was discovered that a small number of soldiers armed with belt-fed machine guns could repulse attacks by much larger numbers of enemy soldiers.  Machine guns permanently changed the face of warfare, making frontal assault by infantry suicidal.

In effect, James Paddock transformed his hotel room into a machine gun nest.  From his position on the 32nd floor of the Mandalay Bay, he could murder and maim with impunity.  Unlike previous mass shooters, he didn't have to worry about his victims fighting back.

Grant Duwe, research director for the Minnesota Department of Corrections, is an expert on mass public shootings.  His research led him to conclude that these atrocities have not become more common, but they have become more lethal.  This supports the contention that mass shooters have become more effective by studying past shootings.

Las Vegas represents a terrifying new development that could easily inspire copycats.  Unfortunately, the problem of mass shootings has no obvious solution.  As Lankford and Madfis suggest, the media could stop giving mass killers the attention they crave.  Law enforcement could also develop more effective tactics for stopping mass shooters.  While these are good ideas, neither will do more than mitigate the problem.  Mass shootings will almost certainly remain a problem for the foreseeable future.