U-boats and the Sinking of the Lusitania

Prior to the start of World War 1, Germany was making an effort in developing its naval power to compete with Great Britain's navy. This included the development of U-boats, which the first submersibles built in Germany. U-boats had the advantage that they could stay underwater for long periods of time, thus being virtually undetectable until the later development of radars. With the start of World War 1, Germany began practicing unrestricted submarine warfare, which involved U-boats destroying ships that were seen as a threat to the Triple Alliance. The most infamous example being the sinking of the Lusitania. The RMS Lusitania was a British liner with a carrying capacity of almost two thousand passengers. On May 7th, 1915, a German U-boat attacked the Lusitania without warning, causing it to sink rapidly and claiming the lives of over 1200 passengers, including more than 120 Americans. Germany justified this act after it was discovered that the ship was carrying munitions on board along with the passengers. Despite this, the sinking of the Lusitania played a significant role in turning public opinion against Germany. It also increased political tensions between the United States and Germany, and later prompted the US to join the war in favor of the Triple Entente.