CARSON, Calif. -- The disappointments of 2015 have altered neither the approach nor the convictions of Jurgen Klinsmann and his most vital players, who head into the new year looking to do what they're always looking to do: grow stronger, better, and more consistent.

They've got World Cup qualifiers in March and again in September, plus Copa America, on home soil--a test that at the very least will serve as a measuring stick as the the US men's national team's evolution progress under Klinsmann.

It's all occurring amid increasing scrutiny, which means greater criticism. After the Yanks' failures in last summer's CONCACAF Gold Cup and the CONCACAF Cup playoff with Mexico that followed in October, there have been harsh judgments issued from various quarters.

But none of it has much effect on Klinsmann and his staff's daily toil, and if this year's “January” camp seems something of a reaction to what occurred over the last half of last year, well, it isn't. The importance of qualifying for this summer's Rio de Janeiro Olympics, especially after missing the 2012 London Games, altered the makeup of the roster, with U-23 players composing nearly half the group.

That aside, everything is as it always is.

“The approach doesn't change,” Klinsmann said ahead of the Americans' first two 2016 matches, Sunday afternoon against Iceland (3:45 pm ET, ESPN2, UniMás, UDN) and next Friday night against Canada at StubHub Center. “Our way of guiding the national teams is always helping players wherever we can, explain to them how much we can in order for them to grow, and make them stronger and better every day we work with them. Of course, we need to get the results, and that didn't happen in 2015, because of certain reasons, but then there's always the next opponent.

“Now we get the biggest opponent [with] a Copa America in the United States. It's just huge to us because we can measure ourselves with the Brazils and Argentinas of the world. Overall, we are driving in the right direction, and at the end of the day, the national team's program is the locomotive of this sport in the country.”

It's often difficult to evaluate progress, because results--and often quality of play--aren't always the proper indicators, but poor outcomes in the most important competitions last year didn't provide favorable light.

The US, expected as always to make the Gold Cup title game, lost to Jamaica in the semifinals and fell to Panama on penalty kicks in the third-place game. It proved their worst finish since dropping a quarterfinal in 2000 to Colombia, one of three “guest” teams in that competition.

They then missed the 2017 FIFA Confederations Cup, losing the playoff to Mexico in overtime on Paul Aguilar's brilliant late finish.

“On the inside of the group, I think it's always important to maintain a strong mentality and to not let success take you too high and to not let disappointments bring you too low,” captain Michael Bradley said. “And I think we're certainly aware that we let ourselves down in some big moments last year. But that's sports. You play big games, you play in moments where everything's on the line, and one team has to lose. That's reality....

“We've talked till we're blue in the face about last year. When you compete at the highest level, the margin between winning and losing is very small.... Everyone wants to analyze and dissect, and we do the same, but we do it on the inside, and more than that, it's time to look forward for a good year.”

Klinsmann says that 2015 “kind of went the way that we envisioned it,” with the primary achievements being the additions of LA Galaxy forward Gyasi Zardes and Club America defender Ventura Alvarado to the chief player pool, as well as a decent start to the World Cup qualifying campaign.

Klinsmann has worked to integrate new faces into the pool; 10 players made their international debuts during the calendar year and 16 have since the 2014 World Cup. But it's impossible to predict how young players will evolve. Nearly a dozen have emerged as regular or semi-regular call-ups since 2013, including Matt Besler, John Brooks and DeAndre Yedlin, and several others (Darlington Nagbe, certainly, and perhaps Matt Miazga among them) appear to be headed that way.

Nine players in camp not among the U-23 group have five or fewer caps. Klinsmann was asked if he expected there to be greater player turnover this year.

“Maybe yes, maybe no,” he replied. “The beauty of it is that we try always to inject a new wave of players and give them opportunities and have a very kind of open-door policy. At the same time, the established players are getting forced to prove their point, prove themselves. And so we have see competition [in] every camp that we are together.

“Sometimes there might be an open slot for a younger player, and, boom, he jumps on it and gets in, like a Gyasi Zardes in 2015, a DeAndre Yedlin following his World Cup performances.... But it could also be the other way around, where we say this experienced player, there's no way somebody kicks him out right now, like a Jermaine Jones, for example. A Tim Howard. And so you are as a coaching staff caught in between and say, 'Okay, when is the transition happening in that specific position?' But it is dictated by the performances of the players. It's dictated by the next generation, if they're strong enough.”

The World Cup results in November--a 5-1 home win over St. Vincent and the Grenadines and a scoreless draw at Trinidad and Tobago that, Klinsmann noted, “we should have won”--put the US in position to secure their spot in the hexagonal that will determine CONCACAF's qualifiers in Russia with a sweep of Guatemala on March 25 and 29.

“I think 2015 was a good year,” Jermaine Jones said. “Jurgen tried to see some new faces and maybe make some players in different positions and try some stuff, and some games got well, some games not, and especially the Gold Cup, I think everybody was not happy with the results.

“Now I think 2016, where we started already [World Cup] qualifying, it's more focused. I think Jurgen finds his group and he's focused that we try to come out of the [fourth-round qualifying] group real quick and make it clear that we go to the World Cup.”

Concrete progress will be needed to assuage the critics, but that's not on Klinsmann's mind.

“You have people on the outside who think they can evaluate your work and give their comment,” he said, “but the sign that you get publicly evaluated is a good one, because [it indicates] the interest is growing. If now the critic is right or wrong, that's not the point.

“A coach is always measured on his results. He's always measured on his success rate. So if there's a year where there's a little dip, like 2015, then people will criticize the head coach and think they know it better than we do. And if you have all your positive results, then you say, 'Okay, he's doing a fine job.' That's just normal. It's totally fine for me.”

The big picture is what matters, and that's 2018 and Russia, Klinsmann says. And it extends further, to 2022 and beyond, with construction of the foundation for the US to not only compete in World Cups but to win them.

Bradley cautions that it's “always important to have an eye on the long term, but, certainly for the players, the main focus has to be on a daily basis what we're doing to improve ourselves, what we're doing to make sure that the team continues to move forward.”

“It's always difficult to put a timeline on [progress],” Klinsmann said. “But I think with all the initiatives that [are happening] in this country, [with the] youth-club system, the academy system that is just six or seven years old and will definitely show a huge benefit down the road many, many years to come, to the initiatives of MLS and NASL, the open-mindedness from the college system to [possibly] extend their season....

“You see all these different pieces happening and you want to see a benefit down the road, and you will see a benefit. But to put a timeline on it is very difficult, when some countries like Spain, it took them decades to build what they did."