Traditional combat models such as the Lanchester model are typically limited to two competing populations and exhibit either exponential growth or decay solutions. Although these early models were well suited to the type of warfare in the early twentieth century, they are no longer as directly applicable to the complex modern military operating environment. Despite these shortcomings, the Lanchester model was used in the Operations Research of Force Design even in World War II, as evidenced in the classic work Methods of Operations Research of Morse and Kimball [1950]. Our work seeks to enrich such models to account for modern and future complexities, particularly around the role of inter-agency engagement in operations. To this end, we account for the presence of civilian or non-combatant populations, which have long been an unfortunate part of the combat setting as they are directly impacted by the warfare surrounding them. Typically this non-combatant group consists of the host population in the space where combat occurs. The other type of non-combatant groups, a development since the 19th century and with ongoing evolution today, are agencies, be they governmental or non-governmental, that undertake work in conflict e nvironments t o s upport local populations. Depending on whether they are governmental or otherwise, these agencies have a range of formal and informal relationships with both sides of the conflict. As the agency non-combatant populations play no direct role in combat, their interactions with the two combatant forces are well suited to be modelled through the recent developments in non-trophic ecological models. The networked non-trophic ecological model is one of the most recent developments in ecological modelling that incorporates a great number of positive and negative interactions, both trophic (consumptive) and nontrophic (non-consumptive), between multiple species in a "multiplex" network. In a similar manner in which the Lanchester combat model can be viewed as an adaptation of the Lotka-Volterra model for two species in a predator-prey relationship, the networked non-trophic ecological model can be exploited as a viable representation of modern combat in which non-combatant groups exist. The combat model presented in this paper provides a global representation of asymmetrical combat between two forces in the modern setting where non-combatant populations are present. In our model, the noncombatant population is present as a neutral agency supporting the native population to the extent that they are non-combatants, but where there can be leakage from this group to the insurgent fighting f orce. Correspondingly, the opposing intervention force is under obligations to enable an environment where the neutral agency may undertake its work. A key result of our model is that, in contrast to the typical exponential growth or decay solutions of the Lanchester system, with the inclusion of a third group limit cycles and bifurcations can now occur which we interpret in light of the warfighting app...