The worse mass shooting was done by the US Army at Wounded Knee, 297 dead after they turned in their weapons, most killed were wommen and children
76 men, women, and children were killed at Waco.
“The worse mass shooting was done by the US Army at Wounded Knee, 297 dead after they turned in their weapons, most killed were wommen (sic) and children.”
That was a fight. Some 30 US Cavalry were killed by the Sioux in that fight. Yes, it was lopsided, but still it was a fight. I guess, according to your definition, Normandy Beach on June 6, 1944 was a “mass shooting.”
A larger massacre than Wounded Knee was committed in 1813 by Alabama Creek Indians against whites and westernized Creeks:
https://en.wikipedia.org/wiki/Fort_Mims_massacre
500 people killed.
Saying that Wounded Knee was the largest does not make it so.
May want to look at the 1863 Bear Creek Massacre, the numbers of Shoshones killed may have been as high as 350.