The document discusses how the arms race between European powers in the late 19th and early 20th centuries contributed to tensions and insecurity that helped cause World War 1. It notes that defense spending increased four-fold from 1870-1914 for major powers due to nationalism, imperialism, and fears of being militarily weaker than rivals. Germany and Britain engaged in a naval arms race focused on building the most advanced warships, called Dreadnoughts, further heightening tensions between the two powers as they both sought to expand their global empires and naval strength. The buildup of large standing armies and reserves across Europe through conscription meant the major powers had the military capabilities and suspicions of one another to make a major conflict more