Bell Telephone ran numerous advertisements touting its contributions to the war effort. It also encouraged people not to use the telephone since facilities were overloaded.
Here are some samples from "Michigan Technic" an engineering journal (from google books).
The ads marked "vivid drawing" were part of a series of ads that featured very rich emotional artwork. Other ads of that series appeared in LIFE magazine in color.
Western Electric "telephones are life lines"
building a new cable for defense
Training signal corps
conservation of scarce materials for military use
improved aerial cable suspension
Women serving as operators and manufacturers for defense
communications directing combat
hold it! is this long distance call really necessary?
telephone direction in combat (vivid drawing)
boy manning anti-aircraft using phone (vivid drawing)
telephone in submarine service (vivid drawing)
You may scroll through the rest of the magazines. Lots of neat ads and articles about heavy industrial technology and engineering.