In April 1914, the Mexican situation became more muddled by an American overreaction to a minor incident in the Gulf coastal town of Tampico. Seven uniformed U.S. sailors were arrested for straying into an off-limits area and were paraded through hostile crowds in the town. When the matter was brought to the attention of a higher Mexican official, the sailors were quickly released and an informal apology issued.
The commander of the U.S. Atlantic Fleet, Admiral Henry T. Mayo, was not so easily satisfied and demanded a formal apology and as an act of contrition that Mexico raise the American flag on her soil and provide a 21-gun salute. The Mexican commander responded with a formal written apology, but refused to salute the flag.
On April 20, Wilson, no doubt tiring of "watchful waiting," sought Congressional approval for armed intervention in Mexico. The Tampico incident was cited as one of a list of contributing causes. Congress responded affirmatively two days later.
the Creole Incident At sea its cargo of slaves mutinied and took over the vessel, then made for the Bahamas, where the mutineers were arrested and the crew allowed to go free. Secretary of State Daniel Webster, arguing that the slaves were on an American vessel and ... http://www.usahistory.com/wars/creole.htm