The last of the 32 captains announced for this year's World Cup, Adams is only the second under 30 years old. England forward Harry Kane is 29 and has captained the Three Lions since the 2018 World Cup, when he was 24.
United States coach Gregg Berhalter made the annoucement Sunday, the day before the Americans play Wales in their first World Cup match since 2014.
``He leads by his actions and his words,'' Berhalter said.
Adams, from Wappinger, New York, has captained the national team nine times previously, including seven wins, one loss and one draw.
Berhalter had rotated the armband since he was hired in December 2018. Christian Pulisic has captained the Americans 11 times, including seven victories, one defeat and three ties, and Walker Zimmerman has captained the United States six times.
Adams was captain in seven of 14 World Cup qualifiers, Pulisic four and Zimmerman three.
Different players captained the United States national team for each game in 1950. Bahr was 23 years, 3 months, 2 days for the 5-2 loss to Chile on July 2, 1950. Adams will be 23 years, 9 months, 8 days on Monday.
Ed McIlvenny (25) wore the armband for the famous 1-0 upset of England in Belo Horizonte and Harry Keough (22) for the opening loss to Spain.
Previous World Cup captains included 24-year-old Mike Windischmann in 1990, 25-year-old Tony Meola in 1994, 37-year-old Thomas Dooley in 1998, 28-year-old Claudio Reyna in 2002 and Reyna again in 2006, 31-year-old Carlos Bocanegra in 2010 and 31-year-old Clint Dempsey in 2014.
Earnie Stewart, then 33, captained the United States in the 2002 opener against Portugal because of Reyna's strained right quadriceps.
``We're not a group of guys that it's like, oh, I want to be captain,`` Weston McKennie said Saturday. ``Whoever has it, has it. The mission is still the same. The goal is still the same, and we just need all 26 players no matter their role to be on the same page and have the same role at the end of the day, which is to compete and win games.''
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