Jürgen Klinsmann is grinning. The German footballing legend, now USA head coach, is watching the under-21s go through their warm-ups at a national federation training facility in Carson, California. Occasionally, Klinsmann will stride forward, with that slightly lupine gait familiar to defenders from his playing days, and bark an impatient order, only to leaven it with that equally wolfish grin.

Klinsmann does this a lot – grin. That and giggle. He will throw out a faintly damning comment, or say something about the scale of the challenge facing the game in the US – “We are still a few years away!” – only to grin broadly as he does so, or utter that high-pitched giggle, as though it is silly to even worry about it.

Klinsmann needs all of his lightness of touch in cajoling his USA team through a daunting World Cup group later this month. His side will be paired with their 2006 and 2010 nemesis Ghana, Cristiano Ronaldo’s Portugal, and (with a certain inevitability) Germany.

He’s still youthful, still reminiscent in many ways of the player who instantly disarmed English fans reared on the image of him as the face of dour Germanic footballing efficiency and underhand gamesmanship, by diving full length to celebrate his first goal in the Premier League with Tottenham. That said, the two decades spent mostly in California — he credits childhood holidays and an American wife for making the USA feel like “always a second home” — have not noticeably chilled him. He was always like this.

Klinsmann became the USA coach in 2011, replacing the American Bob Bradley. He had been a long-time target for the president of US Soccer, Sunil Gulati, who admired how Klinsmann had inspired a young German team in 2006. But it was not until Klinsmann’s abortive stay at Bayern Munich had ended in 2009 and Bradley was deemed to have taken the squad as far as he could after the 2011 Gold Cup that Gulati got his man.

Initial results on the field were indifferent, although the root-and-branch reform of the technical side of US Soccer that Klinsmann was also charged with got under way immediately and the results began to follow (away wins in Mexico and Italy stand out). “You realise that a lot of those dots aren’t connected yet, especially in the area of youth development,” Klinsmann says.

“It [the organisation of football] was still connected to the other big American sports, where there are seasonal sports – four, five months this game, then you play basketball, then you play baseball. So they don’t have the 10/11-month seasons like the football powerhouses in the world. USA kids never really develop that rhythm of the game in the same way, the stamina and the pure focus on the game.

“No matter what level we’re involved at, it’s trying to connect the dots – we’re trying to connect coaches’ education, we’re trying to connect player development, we’re trying to connect the professional league to the bigger picture, the international picture. So – and this is all changing over the past couple of years – we introduced an academy system with a 10-month season. MLS extended their season longer and longer in order to become more competitive.”

He rolls his hands to indicate progress. These long-term goals are part of what makes Klinsmann’s job unique and his power to influence strategy far-reaching. He was recently given a contract extension to 2018, suggesting that the results of the World Cup won’t determine his fate, unlike other coaches who live and die by World Cup cycles. Yet Klinsmann says: “The competitor in me knows that the World Cup is the benchmark”.

The USA start with a difficult game against Ghana and, given the next two outings are against Portugal and Germany, it seems a must-win game. He partly agrees – calling the game “kind of a final” but also says: “if it’s a tie at the end of the day, we’ll adjust to it – it’s no problem. Nobody will panic. We’ll say, ‘OK, they [the USA] have got to do what they did in 2002 in beating Portugal.’ Anything is possible in a tournament and we will prepare in the best way we can in order to surprise a few people out there.”

In their own bid to avoid surprises the USA spent their January camp in Brazil, at the hotel and training centre they will use during the World Cup. Klinsmann claims such preparatory details help give “peace of mind” but also speaks of the typical US player’s ability to adjust amid the environment and scale of Brazil.

“I think our players – travelling, no problem. Adjusting to different circumstances – no problem. Fly three and a half, four hours from one place to another, and it’s no big deal. Because we’ve played in Honduras, Costa Rica, Panama … for us, qualifiers are a grind that you’ve got to go through. You go to San Pedro Sula [Honduras], and you have two days to prepare and you get out of the aeroplane and you can’t breathe because it’s 95F and 98% humidity, and the sticky air and the smog, it’s … ugh. And the highest crime-rate city in the world doesn’t really help you! So we are used to adjusting to different circumstances and this is how we’re going to approach Brazil. We always say it’s two teams on the same field, same circumstances, so it’s who can adjust better to it.”

Klinsmann’s adjustments will continue to the last minute. He’s tried to put together the toughest schedule of friendlies he can in his time with the team but a further logistical challenge of his job means it’s hard to maintain consistency outside of tournaments and qualifiers. Of the dispersal of players and staggered seasons in the US, Mexico and Europe, he says: “it’s very different to the work of England or Italy or Germany, where you always have your key 16, 18, 20 players together. For some games I might have 20 players that might not even be part of the World Cup.”

Early signs, not necessarily attributable wholly to Klinsmann’s regime, suggest that the domestic league, at least, is contributing more players to the national team. Four MLS players travelled to South Africa with the national team in 2010. Fifteen have made the provisional 30-man roster for 2014. This sounds like progress.

“The league is making big strides but you still compare yourself – ‘OK what are we lacking compared to the big leagues and the big countries?’ And it’s consistency. It’s that you live this game day in, day out; it’s become part of your culture, your way of life; your mindset is driven by it. And there we still have to realise that we’re not there yet,” he breaks out in another giggle.

“By no means do we have the social environment where a professional player loses a game and the next day he gets bothered by the fans when he goes to the butcher, the baker, the supermarket. We don’t have that kind of accountability and this is what we would love to have one day. But it will still take a few years.”

Still, that development side of Klinsmann’s job, particularly trying to make a Balkanised US youth system to cohere, is the part of his remit he finds most fascinating and rewarding – citing the young German players he worked with between 2004 and 2006 and how they still call him to thank him for improving them. He is reminded of the pressure he was under from the German media in the lead up to that 2006 tournament and, ultimately, the relief when his youthful team not only surpassed expectations but seemed to usher in a new prototype of attacking German football. What did he learn from that time that he is trying to instil in his American charges now?

“Every experience, every talk you have with people in your environment, you learn. If it’s not the two years I guided Germany, or it’s the one year I worked at Bayern Munich, you learn constantly and you see things differently than maybe you did eight years ago. But also the circumstances are different, the next generation of players are different. The way they function, the way they look at life, look at their profession, is different to what it was 10 years ago. We live in the social media world now. They’re busy with their cell phones, with Twitter, Facebook, Instagram, so we’ve got to figure out as coaches, you know, ‘How do we communicate with them? How do we get to them to make them understand what is important, what is not important?’”

Klinsmann claims to have told every player in the national set-up from the under-14s upwards that they can reach out to any of the coaching staff, including Klinsmann himself, to clarify the expectations for them. “By email, by text, by Twitter, by Facebook, whatever, you want to do we’ll be there. So you can’t say a couple of years down the road, ‘Oh if I’d known that’.”

Klinsmann is laughing ruefully as he says this and then again a moment later when asked about England’s prospects: “We talk about the qualities of the English team and the qualities are, without any doubt, always there. I wish they’d put their mark on a huge tournament because the Premier League and their players are admired all over the world but at a certain time you have to prove it at the highest, highest level, and that’s the World Cup.”

And Germany? This time the smile is cautious: “Germany’s a side that can win the World Cup, is among the top three right now in the world and it’s also a very special generation that is there, but at the end of the day that generation has to put the dot on the i to make the final step to win a competition like that – otherwise you go down as an amazing generation without winning a big tournament.”

Few are expecting the USA to win the World Cup but, equally, for all the talk of “connecting the dots” and long-term success, any coach’s tenure can be undermined by a bad tournament. “Well, you want both to happen – success in Brazil then continuing the long-term growth of the game and the players here.

“But you also have to be measured on the short-term results. Obviously, I’m convinced we’ll get the results but if not and let’s say things go really the wrong way, and the federation decide to bring in a new coaching staff, I want to at least be sure that we have laid out the foundation.”

He gives another big laugh as he dismisses this negative prospect before striding across the field to his young players, already set to bark orders and encouragement in his cheerfully hectoring manner. “But if it’s someone else, that’s the way of life!”