The UH-1N (recently entering the game under the Canadian guise of CH-135), was also purchased by the U.S. Air Force and Marines as one of its first customers. The Air Force specifically uses it for utility and patrol duties primarily at ballistic missile sites,.
In the contexts of WARNO, the UH-1Ns would perform the role of patrol helicopters, but allow for an enhanced lore experience. If given to the large USAF patrol squad, it could be mentioned that wartime threats prompted the deployment of Security Force units from northern contiguous bases within the United States; their purpose would be to bolster the defense and security of Elmendorf Air Force Base and other local facilities.
Practically, if given to the USMC security squad, it would allow for seven (eight?) capable assault squads to be air-deployed, giving the division more tactical and strategic options across all gamemodes; both branches armed their UH-1Ns with door guns of some variety but no rockets, allowing for American UH-1Ns to be distinct from the Canadian CH-135 in a way that still affects gameplay.
Aesthetically? It looks cool in green.