Final answer:
Bugs Moran, leader of the North Side Gang, was the intended victim of the St. Valentine's Day Massacre but escaped because he was late to the meeting spot where seven members of his gang were executed.
Step-by-step explanation:
The intended victim of the St. Valentine's Day Massacre was actually Bugs Moran, the leader of the North Side Gang, an Irish-American criminal gang in Chicago. On February 14, 1929, seven members of his gang were lined up against a wall and shot by four men using weapons including Tommy guns. Although Bugs Moran was the target, he escaped the assault because he had arrived late to the meeting spot, a garage at 2122 North Clark Street. The massacre is believed to have been organized by Al Capone's South Side Italian gang to take control of organized crime in the city.