Camp Lejeune | ITB Week 9

The Making Of An Infantry Marine

“Patrolling and Defense – Building Endurance and Tactical Confidence”

Forging Endurance and Tactical Awareness

Week 9 represents one of the most physically and mentally demanding stages of training. Marines begin the week with a 20K conditioning hike, a test of endurance and determination that reinforces their strength, discipline, and commitment to one another.
Following the hike, the focus turns to Patrolling and Defensive Operations — where every Marine learns how to plan, move, and fight as part of a cohesive combat unit.

Through long hours of movement, defensive drills, and night operations, Marines gain confidence in their ability to sustain themselves, their gear, and their teams under stress. This week builds not just endurance, but trust — the kind that defines every successful Infantry unit.

0311 – Riflemen

Riflemen execute the 20K hike before transitioning into Patrolling and Defensive Operations, learning how to conduct security halts, establish fighting positions, and respond to contact. Instruction focuses on movement formations, fire team coordination, and how to plan and occupy defensive sectors.
These exercises develop tactical awareness, leadership, and endurance — qualities that turn individual Marines into disciplined members of an integrated platoon. Each day in the field reinforces teamwork and resilience, proving that readiness is built step by step, mile by mile.

0331 – Machine Gunners

Machine Gunners begin the week with the 20K conditioning hike before transitioning into .50 caliber machine gun classes and practical application. The M2 .50 caliber machine gun, a weapon known for its reliability and dominance on the battlefield, weighs approximately 128 pounds when fully assembled and can engage targets effectively beyond 1,800 meters.

Instructors introduce its role as a heavy machine gun platform, capable of delivering long-range, high-volume suppression in both offensive and defensive operations. Marines study the weapon’s characteristics, mounting options, and the importance of precision in crew coordination.

During practical application, students work as gun teams to refine communication, gun emplacement, and engagement procedures under the guidance of experienced Combat Instructors. This training highlights the balance of strength, teamwork, and technical skill required to manage a weapon of such power.

By the end of the week, machine gunners gain a deeper appreciation for how the M2 anchors the defense, protects maneuvering elements, and delivers unmatched firepower — proving that disciplined teamwork and precision remain the hallmark of Marine Corps lethality.

0341 – Mortarmen

After completing the 20K hike, mortarmen transition into 60 mm mortar instruction and live-fire application. Classroom blocks cover tactical employment, range safety, and communication between forward observers and the gun line.
Under instructor supervision, Marines conduct practical applications and live-fire events, refining their ability to provide timely, accurate indirect fires in support of maneuvering elements. These training evolutions demonstrate how mortars serve as the backbone of close-support fires, giving commanders flexible, responsive options in dynamic environments.

0352 – Anti-Armor Marines

Anti-Armor Marines begin with the 20K hike before focusing on Javelin and Saber classes, along with armor identification training. Classroom instruction emphasizes target recognition, engagement principles, and the integration of anti-armor teams within the larger maneuver force.
Through guided practical application and simulation exercises, Marines gain confidence in identifying, tracking, and reporting armored threats — and understanding how to employ precision fires that neutralize enemy armor and safeguard friendly units. This week highlights the decisive role of anti-armor Marines in shaping the battlefield and protecting the force.

Integration and Purpose

Across all MOSs, Week 9 reinforces endurance, tactical decision-making, and team cohesion. From the 20K hike to the long hours in patrolling and defense, every event teaches Marines how to endure fatigue, communicate under pressure, and execute their mission with precision.
By week’s end, they not only know how to defend and maneuver — they understand what it means to depend on each other when it matters most.

Semper Fidelis,
SgtMaj Paul Davis, USMC (Ret.)