In time, the true costs of World War I were revealed. Wounds of war included fourteen million people—civilians and combatants—killed; over $3 billion spent; four empires destroyed; the world map changed by revolution and treaty; and an unknown loss of spirit for many. Twenty years after the Armistice, many World War I soldiers felt the need to look back over their shoulders and wonder. Was the world really safe for democracy? Had the war ended all wars? The questions were answered, and their idealism was shattered when war broke out again in Europe in 1939.