The Argentine, the former Tottenham Hotspur and Paris Saint-Germain coach, was unveiled to the media on Friday after signing his deal this week.
The USA is co-hosting the 2026 World Cup with Mexico and Canada and Pochettino said he believes the target should galvanise the players.
"We need to believe we can win. Not win just a game, but to win the World Cup. We want players to arrive on day one thinking big," he said.
The USA's best finish in a modern World Cup was a run to the quarter-finals in South Korea and Japan in 2002. The country finished third in the inaugural tournament in 1930.
The US Soccer Federation turned to Pochettino after sacking coach Gregg Berhalter following a poor showing in June's Copa America.
With no qualifiers for the host nation, the only competitive games for the USA will come in CONCACAF's regional Nations League and Gold Cup tournament.
The coach, who most recently worked at Chelsea, has less than two years to turn around the fortunes of a team which has won just one of their last seven games but he believes that he can do it.
"I believe there is enough time. We can't use this as an excuse," said Pochettino who said 'belief' was the single most important factor in the process.
Pochettino also made clear he would have a completely open mind towards team selection.
"To every single player that is around the world, we are going to try to pay attention. They have the door open...if they perform we are going to be there watching," he said.
The Argentine said that the job appealed to him, among other reasons, because it was a different challenge.
"As a staff we've had a lot of experience as coaches already in different clubs... this is a challenge that takes us out of our comfort zone... not only to achieve things together but to refresh ourselves in a soccer that for us was always attractive from afar," he said.
