Reading about the hunt for the wreck reminded me of how modern history is rife with examples of one country’s acquiring its adversaries’ weapons, reverse-engineering them and then using them against their creators. I recently came across the unpublished memoir of the Nazi weapons engineer Herbert Ruehlemann, who described how this dynamic played out in the late 1930s: “As soon as you introduce a new weapon in war, the enemy always gets ahold of it.”

In this instance, he was referring to electric bomb fuzes that he had personally designed and that were dropped by German pilots during the Spanish Civil War, between 1936 and 1939. When the Nazis invaded Paris, German intelligence officers found reports indicating that French engineers had acquired these fuzes in Spain and tried to reproduce their own copies.

Ruehlemann himself came to America in 1948 as part of Operation Paperclip, a secret program to locate and recruit German scientists and engineers to work in the United States following World War II. He was sent to the Naval Ordnance Laboratory in White Oak, Md., to continue his work on bomb fuzes for Uncle Sam.

At the same time, the end of World War II gave the Pentagon and American intelligence agencies opportunities to steal its adversaries’ secrets whenever and wherever possible — including off the seafloor. When a Soviet submarine sank 1,560 miles northeast of Hawaii in 1968, the Navy found out about it, and observed that Soviet search-and-rescue efforts failed to locate the wreck.

In 1974, the C.I.A. raised part of that sunken submarine without the Soviet Union’s knowledge, using a ship called the Hughes Glomar Explorer. The vessel hovered over the wreck site and lowered a clawlike apparatus to the bottom of the ocean, grabbing onto a section of the submarine’s hull that was then raised into the Hughes Glomar Explorer’s belly.