Shooting in Idaho fast food restaurant

Last Saturday, a deranged 24 year old man opened fire on innocent unsuspecting victims, 3 total, and wounding at least 10 more. The assailant initially targeted an employee, a 23 year old woman, at In-N-Out, working her cash register position. He then killed a 59 year old, who had been in his vehicle for the drive through. Employees scrambled to the initial victim, while dodging incoming bullets. Several more were injured unfortunately, inside the restaurant, after his initial attack at their Drive Through - An armed citizen returned fire, as the gunman subsequently slaughtered an innocent man charging his Tesla vehicle, and almost mortally injuring his wife.

This terrible incident, which has wreaked chaos and agony to the town of Twin Falls Idaho, once more represents what dangers everyday Americans face on a daily basis.

I'm especially enraged at the cowardice of this random ambush; how a woman merely doing her job at the cash register, can be killed in such an unacceptable, humiliating manner. May she, Ashley Garibay, and the two other victims senselessly murdered rest in peace.

What can be done to prevent these violent atrocities from happening?

Props to the civilians acting, 2nd Amendment protected, against an imminent life threatening scare and fighting off this evil predator;

https://abcnews.com/US/victims-burger-shooting/story?id=135352228