What replaced the close-support bombardment monitor?
Short answerA combination of 4.5-inch naval guns, aircraft, helicopters, and smaller boats.
NotesThe answer points to the 4.5-inch gun on a modern destroyer or frigate as the direct naval-gun replacement. Aircraft, helicopters, and boats supply the rest of the close-support package. It also notes that monitors depended on sea supremacy because they existed to support forces ashore rather than win control of the sea themselves. The mission was therefore dispersed across several platforms rather than inherited by a single successor class.