But let’s start with the worst: Mass killings harming 10 or more people.
As of Oct. 2, 2017, there have been 50 such incidents in the past 3 decades, including Sunday’s mass shooting in Las Vegas. The above sources and other experts have broadly sorted these into categories:
24 were considered domestic terrorism. 9 of those were attributed to Islamic extremists. Another 15 were attributed to political, anti-government or Christian extremists. And of course, we don’t know the motive of the Las Vegas killer yet.
34 were mass shootings.
8 were bombings.
Other methods of killing included arson, train sabotage, anthrax, knife, vehicles and small airplane.
Since 1986, there have also been 2 international terrorist attacks on U.S. soil in which 10 or more people were injured or killed.
The Sept. 11, 2001, airliner attacks killed nearly 3,000 people and injured more than 6,000. The World Trade Center truck bomb on Feb. 26, 1993, killed six people and injured more than 1,000.
Again, there are broad categories that define all this.
International terrorism consists of attacks committed on U.S. soil to further an ideological, religious or social cause in which the perpetrators are not citizens of the U.S. or were not lawfully admitted to this country.
Domestic terrorism accounts for similar attacks, but perpetrated by U.S. citizens or people who are here legally, including on visas.
Then there’s mass murder: Motives aren’t political or religious, but can include revenge. Crimes driven by mental illness also end up here.
The 10 deadliest mass murder or domestic terror attacks on U.S. soil since 1986
1. Oklahoma City, Oklahoma: A U.S. citizen born in New York bombed a federal building on April 19, 1995, killing 168 people and injuring 675. He was convicted and executed by lethal injection on June 11, 2011.
2. Las Vegas, Nevada: A U.S. citizen living in Mesquite, Nev., fatally shot at least 59 people and injured at least 500 more on Oct. 1, 2017, before killing himself.
3. Orlando, Florida: A U.S. citizen born in New York fatally shot 49 people and injured 53 in the Pulse nightclub on June 12, 2016, before police killed him.
4. Blacksburg, Virginia: A foreign national born in South Korea shot and killed 32 people and injured 17 at Virginia Tech on April 16, 2007, before killing himself.
5. Newtown, Connecticut: A U.S. citizen born in New Hampshire shot and killed 20 children and six adults at Sandy Hook Elementary School on Dec. 4. 2012, before killing himself.
6. Killeen, Texas: A U.S. citizen born in Pennsylvania shot and killed 23 people and injured 20 at Luby’s Cafeteria on Oct. 16, 1991, before killing himself.
7. San Bernardino, California: A U.S. citizen born in Chicago and a Pakistani in the U.S. on a K-1 fiancé visa shot and killed 14 people and injured 22 on Dec. 2, 2015, before police killed them both.
8. Edmond, Oklahoma: A U.S. citizen born in Oklahoma shot and killed 14 people and injured six in a post office on Aug. 20, 1986, before killing himself.
9. Fort Hood, Texas: A U.S. citizen and Army major born in Virginia fatally shot 13 people and injured 30 others on Nov. 5, 2009. He was convicted, sentenced to death and is awaiting execution.
10. Aurora, Colorado: A U.S. citizen born in California fatally shot 12 people and injured 70 others in a movie theater on July 20, 2012. He was convicted and given 12 life sentences.
Compiled by Associated Press, McClatchy and other media reports.