The deterrent effect comes from imposing bad choices rather than making Allied shipbuilding impossible. Britain would have to decide whether to complete Vanguard and the remaining King George V ships, revise them, or begin a larger design. American leaders would face the same problem with the South Dakotas and Iowas while public comparisons emphasized Yamato's 18-inch guns. Even the United States lacked unlimited slipways and capacity to complete, redesign, and replace all of those programs simultaneously. Japan could not win the industrial contest, but publicizing Yamato might consume Allied time and resources before the war.
Notable Point · 2:26:03-2:29:21
A public Yamato forces an Allied shipbuilding dilemma
Yamato's disclosure could force Britain and the United States to choose among completing, redesigning, or replacing battleships already under construction.