The warfare shown here was a mix of that from WW1 (trenches, dirigibles, gas, no hen's land (no man's land) and new technology (airplanes and modern ships, including an aircraft carrier). WW2 was not far off, which would significantly change how conflicts were fought.
Despite the numerous silly sight gags, the nature of this short is decidedly on the adult side. Cartoons were shown as part of a movie show at the time, to both adults as well as juveniles. So they were made to appeal to both types of audiences.