Today, I’m a classroom teacher, which is not only a challenging job, but an isolating one as well. The classroom is what defines the school day—teachers do not work regularly with other teachers, but rather spend our days working with students behind the classroom door. Every day that I come to school I work with students in a solo capacity. The type of teamwork that defined mission success in the Marines is not required by school administration for a teacher to perform the necessary functions of the job, but will be required and necessary if teachers are instructed to take armed action against an active shooter. As a former Marine and current teacher, I know that building within teachers (including military-veteran teachers) the required teamwork to be effective in a Parkland-type situation is an unreachable goal.

Beyond that collective mindset, the Marine Corps has always emphasized marksmanship. Every Marine is a rifleman first, regardless of his or her specialty. Before recruits set foot on a rifle range for live-fire exercises, proper weapons-handling skills and the fundamentals of marksmanship are drilled into them—and these 13 weeks of training represent a minimum level of proficiency needed to simply be functional in a combat environment. The ability to enter a building and effectively clear rooms—a skill needed to stop an active-shooter situation—requires an added layer of training and specialization. Thus, having military training alone does not guarantee a person to be effective in an active-shooting situation; efficacy stems from the advanced training that particular units receive, such as that which infantry battalions and special-operations forces undergo.

These units train hard to ensure they’re effective in close-quarter battle, learning to fire weapons effectively under repeated stress. They fire thousands of rounds of ammunition in myriad environments during these courses. The purpose is clear: Through repetition and the introduction of stressors, muscle memory is developed; in an actual combat scenario, reaction is almost instinctual. The training required for effective operational response to a hostage situation, for example, requires a high level of training that builds an almost telepathic level of communication, teamwork, and split-second reaction.

Over the course of my time in the Marines, I trained on various heavy machine guns for the purpose of convoy operations, and consider myself to be proficient with a firearm. But none of the skills I learned would truly transfer into an active-shooter situation. Furthermore, as a teacher, I know that most of my day is spent alone in a classroom with my students. Efficient communication—the type forged in the military and necessary for neutralizing an active shooter—cannot occur when teachers spend the day cut off from other teachers in separate rooms.