Emotion and sorrow for the actual victims aside, this isn't even a mass shooting. My understanding is that three people have to die for it to qualify as such, and the shooter is expected to live (they shouldn't count the shooter, but they do anyway). Boise ain't got nothing on a weekend evening in Chicago.
You're confusing mass shooting with mass killing, which is understandable, because there are multiple definitions that aren't used consistently. But check out the (my) bolded section near the bottom...
This is from (OH MY GOD NO!) Wikipedia...
"There are a variety of definitions of mass shooting:[6][7]
*Under U.S. federal law, the Attorney General – on a request from a state – may assist in investigating “mass killings,” rather than mass shootings. The term is defined as the murder of four or more people with no cooling-off period[8][7] but redefined by Congress in 2013 as being murder of three or more people.[9]
*In “Behind the Bloodshed”, a report by USA Today, a mass killing is defined as: any incident in which four or more were killed, including familial killings.[10] This definition is also used by the Washington Post,[11] and similarly Mother Jones defined it as a single attack in a public place where four or more were killed, but have since 2013 changed the threshold to three or more victims being killed due to federal mandate used in an investigation on mass shootings that was initiated by former President Barack Obama.[12]
*A crowdsourced data site cited by CNN, MSNBC, The New York Times, The Washington Post, The Economist, the BBC, etc., Mass Shooting Tracker, defines a mass shooting as any incident in which four or more people are shot, whether injured or killed.[13][14]
*According to the Investigative Assistance for Violent Crimes Act of 2012, signed into law in January 2013, a mass killing is defined as a killing with at least three deaths, excluding the perpetrator.[15][16]
*CBS defines that a mass shooting is an event involving the shooting (not necessarily resulting in death) of five or more people (sometimes four)[17] with no cooling-off period.[13][17][18]
*Crime violence research group Gun Violence Archive, whose research is used by all major American media outlets, defines mass shooting as “FOUR or more shot and killed in a single event [incident], at the same general time and location, not including the shooter,” differentiating between mass shooting and mass murder and not counting shooters as victims.[19]
*Though there are several different definitions of a mass shooting, there are also certain inclusions and exclusions. University of Pennsylvania says no matter how many people are killed, if a shooting occurs by a foreign terrorist that is not included. Another exclusion is if 10 people are shot but only 2 die. Also if 5 people are run over by a car that does not count because no firearm was used. Some inclusions are multiple deaths caused by an armed robbery. Deaths as a result of gang wars are also sometimes included.[20]
The lack of a single definition can lead to alarmism in the news media, with some reports conflating categories of different crimes.[21]
An act of mass shooting is typically defined as terrorist when it “appears to have been intended” to intimidate or to coerce people;[22] although a mass shooting is not, in itself, an act of terrorism.[5]"