Johnson also played for the United States men's national soccer team from 2004 to 2014, and was part of the U.S. squad for the 2006 FIFA World Cup.

After returning to MLS in August – he scored only five goals during the season – Johnson re-injured his toes in mid-September and was sidelined until January 2006.

[4] In 2006 and early 2007, Johnson suffered a decline in form, scoring only twice in the 2006 MLS season and failing to make an impact with the national team.

However, Johnson returned to form with the start of the 2007 MLS season, notching twelve goals and three assists in his first eleven games.

[5] However, after MLS accepted a $6 million bid from Derby, Johnson reportedly nixed the deal as he preferred to finish his season in Kansas City.

[8][9] He joined Championship side Cardiff City on loan for the 2008–09 season in August,[10] making his debut for the club during a 2–1 victory over Milton Keynes Dons in the Football League Cup.

However, he regained some of his form as the season progressed, and had a breakthrough week when he scored his first goal in English soccer on March 7, 2009, in a 3–0 victory against Doncaster Rovers.

[16] He made his Greek Super League debut, appearing as a second-half substitute against PAS Giannina F.C., on January 17, 2010.

He was selected to the 2012 MLS All Star Team by coach Ben Olsen, eventually scoring the game-winning goal against Chelsea in a 3–2 victory.

[21] Johnson led the Sounders in goals scored during the 2012 MLS season, netting 14 total and finishing sixth in the league's Golden Boot race.

[22] Johnson scored the winning goal for the Sounders against Tigres de la UANL in the quarterfinal of the 2013 CONCACAF Champions League knockout stage.

With the Sounders victory over Tigres, they became the first MLS side to eliminate a Mexican club in the history of the CONCACAF Champions League.

[24] Salary cap issues prevented Seattle from offering this, and so Johnson was cut from the team with the intention of his rights been traded.

This success continued at U-20 level, and in 2003 at the FIFA World Youth Championship in the United Arab Emirates he scored four goals, three from the penalty spot, and notched one assist to win the tournament's Golden Shoe as the top scorer.

In the U.S.'s opening Copa América match against Argentina he earned and then converted a penalty kick to put the United States ahead 1–0 in a game they eventually lost 4–1.

[31] On May 11, 2010, Johnson was named to the United States pre-2010 FIFA World Cup roster; he was ultimately cut before the team traveled to South Africa.

Johnson scored the second goal for the United States against Panama during the World Cup Qualifying match held in Seattle, Washington on June 11, 2013.

The goal was scored at CenturyLink Field, the home stadium of his pro club, Seattle Sounders FC.