How was the Mexican American war fought?
It was fought in a manner very similar to the Napoleonic Wars, with armies seeking to defeat each other in a series of encounter battles, but there were many small unit skirmishes and guerrilla fighting as well. The “flying artillery” of the US could be brought into battle very quickly, and the Colt revolver was used in small numbers toward the end, but in nearly all respects it was a very conventional war.