Why did Japan favor torpedoes before gunfire at night?

Did the U.S. Navy learn to launch torpedoes before revealing its position with gunfire?

Not as a general doctrine; Japanese night fighting emphasized concealed long-range torpedo attacks, while American and British practice leaned more heavily on radar-assisted gunfire at close range.

A Japanese long-range torpedo ambush differed from American and British gun-centered night fighting. Long Lance torpedoes benefited from concealment and from an opponent continuing predictably toward the salvo. Radar instead encouraged the Americans to close rapidly and delay gunfire until the range was extremely short. At Blackett Strait the engagement fell to about 4,000 yards, a fraction of the cruisers' six-inch gun range, so the American method emphasized immediate radar-directed gunfire rather than waiting for torpedo results.