Guadalcanal proved that the US Navy could, with losses, take on the Japanese at night fighting. American gunnery and small unit tactics matured and by the end of the campaign proved to be efficient offensive threats, much as Midway proved the effectiveness of US naval airpower.
At the Battle of the Coral Sea, the Japanese won a tactical victory, but suffered an operational-level defeat: it did not invade Port Moresby in New Guinea and set up a base from which its land-based planes could dominate the skies over northern Australia.
