The gap between a nearly 32-knot destroyer and an 18-knot battleship turned speed into operational freedom. Even a three-knot margin helps choose the timing of an engagement, while larger multiples increasingly control position, pace, and disengagement. A foreign fleet arriving off Japan could be slowed further by hull fouling after a long voyage, pushing the practical gap toward fifteen knots. At that point destroyers could move in and out of an enemy defensive envelope with considerable freedom. Japanese commanders could reinforce the armoured cruisers, help the battleships finish their engagement, or threaten a different target, forcing an attacker to bring a complete and balanced fleet. These early destroyers achieved that leverage while displacing no more than about 450 tons fully loaded.
Notable Point · 23:41-27:42
Destroyer speed becomes a tactical weapon
A speed margin approaching fifteen knots over a travel-worn battle fleet gave Japanese destroyers freedom to choose their targets and reinforce either part of the 6-6 battle plan.