Mexican Revolution revolution was in 1914, during the "Ypiranga" incident. When United States intelligence agents received word that the "Ypiranga", a German merchant ship, contained illegal firepower for Huerta, President Wilson ordered American troops to the port of Veracruz to stop the ship from docking. Wilson never actually declared war on Mexico. The United States skirmished with Huerta's troops in Veracruz. The "Ypiranga" successfully docked at another port and unloaded the arms, which greatly angered Wilson. The ABC Powers arbitrated and U.S. troops left Mexican soil, but the incident added to already tense Mexican-American relations. In 1916, in retaliation for Pancho Villa's
SMS Dresden (1907) guns. On 15 April 1914, "Dresden" steamed to Tampico on Mexico's Caribbean coast. That month, the German-flagged merchant ship arrived in Mexico, carrying a load of small arms for the regime of Mexican dictator Victoriano Huerta. The United States had put an arms embargo into effect in an attempt to reduce the violence of the civil war. The US Navy intercepted "Ypiranga" on 21 April. "Dresden" arrived, confiscated the merchantman, and pressed her into naval service to transport German refugees out of Mexico. Despite the American embargo, the Germans delivered the weapons and ammunition to the Mexican government on 28