The Ultimates, Vol. 1 #3 (2002)

21st Century Boy
Bruce Banner manages to revive Captain America, who is having a hard time adjusting to life in the 21st Century. He does realize that the country he fought for is still here, and agrees to work on Fury's team as leader. The issue ends with his first public appearance, also depicted in a "live" feed in Ultimate Spider-Man Super Special #1.
Release Date: 2002