Galiardi, a dual citizen of the United States and Canada, chose to represent Team USA and initially attended USA Hockey's 2007 evaluation camp in Lake Placid, New York but was unable to gain selection to the 2007 World Junior Championships. His first foray into the international competition came when he was added to Team USA for the 2010 World Championships following completion of his 2009–10 rookie NHL season on April 29, 2010. On May 7, 2010, he made his Team USA debut in a 2-1 upset defeat in the World record attended Championship opening game against hosts Germany. Galiardi finished with 3 assists in 6 games as the United States slumped to a 13th-place finish.