The document discusses the formation and membership of the Triple Alliance and Triple Entente alliance systems prior to World War 1. It notes that Italy was originally part of the Triple Alliance but joined the Triple Entente in 1915. It also mentions that the USA remained isolated until entering the war in 1917. The formation of the Triple Entente in 1907 is explained as being due to the collapsing Ottoman Empire leaving a power vacuum, and the desire of Russia and Austria-Hungary to gain influence in the region, as well as rising Serbian nationalism and Russia's belief that they shared common interests with other Slavic peoples.