A graduate of the U.S. National Team Development Program, Kesler led his team to a gold medal win at the 2002 Under 18 World Junior Championships and received the tournament's Best Player Award. He played on the United States' World Junior team in both 2003 and 2004 and was instrumental in their success at both tournaments. He scored seven goals in as many games at the 2003 tournament and was a contributing factor in the Americans' first gold medal win the following year.

During the 2005-2006 season, Kesler became a staple on the Vancouver team, then represented the United States at the 2006 World Championships. As a restricted free agent, Kesler signed a deal during the off season with the Philadelphia Flyers for a one-year contract worth $1.9 million. The Canucks matched the offer and Kesler rejoined their roster.

Shortly after the conclusion of the 2006-2007 season, the Canucks signed Kesler for another three years at an average salary of $1.75 million per year.