Modular structuring has become so popular, in fact, that even the US Army has jumped on the modular structuring bandwagon. In December 2004, the 4th Infantry Division of the US Army officially became the Army's newest modular division. Originally divisional-based with unique traditional legacy divisions in terms of design and capabilities (U.S. Dept. of Defense, 2005), the US Army has restructured these legacy divisions into Brigade Units of Action (BUAs) (Anonymous, 2005). The 4th Infantry now has four BUAs whose design is consistent throughout the Army (i.e., a heavy brigade in the 4th Infantry Division mirrors a heavy brigade in the 3rd Infantry (Garner, 2004). Each unit has a portion of all the division staff, and is identical in terms of personnel and equipment (Ziegler, 2005).

Each module is an autonomous brigade, able to function on its own, yet able to sustain another brigade. If one brigade becomes inoperable, there is an identical one available to replace it (Garner, 2004; Ziegler, 2005). Here, the US Army's form of modularization differs from contemporary forms in that instead of a central hub controlling a variety of service providers that perform different functions, the US Army has a central hub controlling services that are exact replicas of each other. Also, it is much more difficult and complex for traditional modular organizations to replace a service provider or partner that has failed, than it is for the US Army who can replace a failed or inoperable unit almost immediately.

The restructuring enables the US Army to tailor their forces toward a more effective fighting force (Garner, 2004), (more command and control, and flexibility and mobility for the division commanders) and quicker mobilization of troops (aided in part, by upgraded software that improves the facilitation of communication, planning and coordination (Ziegler, 2005). The new modular units also enable the Army to produce more combat power through lower soldier turnover because the modularization provides more stability and predictability for soldiers and their families. Lower soldier turnover increases unit cohesion and effectiveness, which increases the unit's combat power (Garner, 2004).