Uvalde Had Prepared for School Shootings. It Did Not Stop the Rampage.

 https://www.nytimes.com/2022/05/26/us/mass-shooting-school-security.html

https://nypost.com/2022/05/25/texas-shooting-salvador-ramos-hs-held-active-shooter-drill-weeks-before-massacre/

https://en.wikipedia.org/wiki/Robb_Elementary_School_shooting#Law_enforcement_failures_and_controversies

https://nypost.com/2022/05/27/cbp-officer-jacob-albarado-runs-into-uvalde-school-with-barbers-shotgun-to-save-daughter/

https://en.wikipedia.org/wiki/Uvalde_High_School