Klinsmann has already used German-born Timmy Chandler and Jermaine Jones, both originally selected by his predecessor Bob Bradley, and he called up Johnson for the recent friendlies against Costa Rica and Belgium although he was not yet eligible to play.
The former Bayern Munich and German national team coach said on Friday he hoped FIFA would complete Johnson's switch of allegiance in time for the October 8 friendly against Honduras in Miami and that he expected other dual citizens to be brought into the U.S. system in the future.
"The dual-citizenship issue is something that is out there for every country in the soccer world," Klinsmann said in a telephone interview with South Florida reporters.
"If you look at what has happened with Germany in the last 10 years, producing a lot of dual-citizenship kids who decided then to play for Germany which gave them a lot of very good players."
Germany focused on immigrants or the sons of immigrants from countries such as Turkey, Poland, Tunisia and that allowed them to bring through players such as Sami Khedira, Miroslav Klose and Lukas Podolksi into the national team.
While Klinsmann did not discuss specific future targets, there are several potential recruits in the Bundesliga, such as Hoffenheim's Daniel Williams and younger talents such as Houston-born Fabian Huerzeler, who is part of Bayern Munich's youth system.
For the U.S., the target is not only the sons of American servicemen in Germany but also players with joint Mexican and U.S. eligibility, such as recent Klinsmann selections Jose Torres and Edgar Castillo.
"It all started really with France in the 1990's - if you look at what team France won the World Cup with in 1998, then you understand how hot the topic of dual-citizenship is," Klinsmann said.
"If they didn't have Zinedine Zidane, [Lilian] Thuram or [Youri] Djorkaeff, I doubt they would have won the World Cup. It is a very important topic for all of us, it is a global race basically."
GLOBAL LIST
Former U.S. Under-20 coach Thomas Rongen researched a list of around 500 players, from youth level upwards, who are scattered around the globe but could be eligible to play for the country.
"Thomas did an amazing job with his list and we have additional information from other people," Klinsmann said.
"I can be of a big help with my network in Europe and in South America and we identify those kids. We have people watching them."
At the 1994 World Cup, the U.S. featured dual-citizens Earnie Stewart and Thomas Dooley, who were born in the Netherlands and Germany respectively, but Klinsmann believes the key now is reaching players early enough to get them into the U.S. youth system.
"I'm not trying to get them straight into the first team at 17, 18 or 19-years-old," he said. "I am a little more conservative on developing those players.
"It is important we observe them in games," Klinsmann said, adding that coaches at Olympic and age-group levels would be expected to integrate them into the U.S. set-up.
