Graf Spee entered the Indian Ocean after avoiding the busiest trade routes and making relatively few individual attacks. On this reading, Langsdorff pursued psychological economic warfare: conspicuous attacks in different areas could spread fear without sinking the greatest possible tonnage. His cautious, restrained treatment of merchant shipping accompanied an effort to avoid vessels that might report his position. The intended political effect was to embarrass the Royal Navy and create public pressure for ships to move south from the North Atlantic. That strategy depended on British reactions to the attacks as well as the physical losses.
Chapter · 52:51-56:22
Graf Spee pursues psychological economic warfare
Selective attacks offered a way to spread fear and pressure Britain to divert naval forces, even with relatively few merchant ships sunk.