Anglo-Japanese treaty, 1902. Concluded to improve British security against France and Russia in the Far East, each party agreed to fight only if the other became involved in war with at least two other powers. The treaty promised to localize any war, and facilitated Japan's decision to attack Russia in 1904. It was renewed in 1905, each party agreeing to assist the other in a war with only one opponent. American objections brought about its demise in 1921-2.