A war with Japan in 1905 could turn the personal union into a wider European crisis. If Germany and Russia remain separate powers and both fight Japan, Britain's alliance obligations are expected to bring it into the war. France could follow Britain, while Austria-Hungary and the Ottoman Empire would have their own interests in the conflict. Access to Baltic, Black Sea, and Pacific ports would still require investment in naval infrastructure. The German Navy's position in 1905, shortly before Dreadnought enters service with Fisher as First Sea Lord, would differ from its position in a later war. The union's constitutional form would therefore help determine which alliances the conflict activated.
Notable Point · 4:54:27-4:58:27
How a German-Russian union could widen the Russo-Japanese War
The union's constitutional form matters if German entry alongside Russia changes Britain's obligations to Japan.