Arena, who had guided the team from 1998-2006 before taking charge of Major League Soccer's Los Angeles Galaxy, was named to replace Jurgen Klinsmann, who was fired Monday after five years in the role.
The Americans lost WC2018 qualifiers 2-1 at home to Mexico and 4-0 at Costa Rica, but their next qualifier is March 24 at home against Honduras, giving Arena time to revamp the squad in his image.
"We'll develop an identity over the next couple of months to build the best team we can be and be ready when March 24 rolls around," Arena said.
"I don't think the roster is going to have radical changes but obviously there will be some. What I really know is how to build a team. I'm hopeful those qualities will allow me to get this team moving at full speed when qualifying starts in March."
While Klinsmann often pitted players against one another to boost talent at every position, the impact hit camaraderie and Arena sees teamwork as a high priority.
"We need to build the chemistry of this team and have a common goal," Arena said. "I believe we have good players. We've just got to get them working together as a team.
"It takes hard work. It takes communication. It takes discipline and it takes some talent. I believe we have enough talent to be in Russia in 2018. It's going to take time, patience and a lot of hard work."
Arena, whose 2002 lineup reached the World Cup quarter-finals before falling to Germany, said the US squad has advanced in the years since his contract was not renewed after a first-round ouster in the 2006 World Cup.
"US Soccer has made great progress, with the growth of the league, the players playing aborad, we have a very good pool of players," Arena said.
"Winning World Cups is a very difficult thing to do. Only a select few teams in the world are able to do that. The US is edging closer to that day. Since I left in 2006, the pool of players has certainly expanded."
Klinsmann pushed that by turning to many foreign-born US players, a move Arena and US Soccer president Sunil Gulati said remains a priority.
"I'm looking forward to our 'foreign nationals' as well as our domestic players," Arena said.
Gulati added, "We're open to anyone, whether they are born abroad or born here," saying neither path was favored in building a US lineup in "Bruce 2.0," a deal struck through the end of the 2018 World Cup.
"I never expected to be back in this role the way it came about in the last 48 hours," Arena said. "The only thing I can tell you is we're going to make it better."
'Game slows down for you'
Arena said he will be better than he was during his first stint as coach, when he went 71-30 with 29 drawn, for having worked with such ex-Galaxy talents as English standouts David Beckham and Steven Gerrard.
"I've learned a lot," Arena said. "I've had 10 years on the field at the club level and the opportunity to work with some of the best players in the world.
"I think 10 years later, I'm better prepared for this job than I was in 1998 and 2002 and 2006.
"You see things a lot clearer and a lot quicker than you did previously. The game slows down for you. I'm quicker at identifying the strengths and weaknesses of players. I'm ready for the challenge of preparing for qualifying."
Arena likes where the Americans are when it comes to the technical level of the sport.
"We're traditionally strong in the goal," he said. "We have some young attacking talent and we have some experience in the midfield. We have to find the right balance and I'm sure we will develop a good team."