US Agent has a comparable origin to Captain America, starting off as a strange reflection of Steve Rogers. John Walker wanted to serve his country, volunteering for a secret experiment, just like The Sentinel of Liberty.
The MCU's new Captain America also shares parts of his origin with Spider-Man.
John Walker first appeared in Captain America #323, by Mark Gruenwald and Paul Neary. It wasn't until Captain America #328, by Mark Gruenwald and Paul Neary, that readers got to see Walker's origin story. While the beginning of Walker's career wasn't exactly like Spider-Man's origin, in Amazing Fantasy #15, by Stan Lee and Steve Ditko, there are thematic comparisons. John Walker wanted to become a hero, enlisting in the army to serve his country.
Even after his service, however, Walker didn't feel like much of a hero. In a similar sense, Peter Parker was an ordinary kid who wanted to break free from his image as a nerdy teenager. Just like Peter, Walker wanted recognition, which he felt he hadn't received yet.
Walker enlisted to have his strength augmented by the Power Broker Corporation and became a member of the Universal Class Wrestling Federation. Peter didn't choose to receive his powers like Walker did, but he did become a wrestler for a brief moment.
Both men were quickly approached by agents who offered them more lucrative careers. John Walker was offered the chance to become a hero, while Peter was given the opportunity to perform on television. Walker was introduced as the Super-Patriot, a new hero who made his name by trying to replace Captain America. As Super-Patriot, Walker worked with others to stage terrorist attacks which discredited Steve Rogers.
Just like Peter Parker, Walker seemed as if he was doing everything for the glory. Peter's television career earned much fame and fortune, in which the web-slinger reveled. Similarly, Super-Patriot's career as a hero was mainly to promote his own values and tarnish Captain America's image. Both origins featured men who wanted a shot at fame and glory above all else.
Eventually, both men became lost in their own publicity and power. Peter lost any care for others, allowing a burglar, who he could have stopped, to run past him. Walker, on the other hand, became the new Captain America, showing much more violent and aggressive tendencies. The new Captain America was also forced to abandon his old partners, Hector Lennox and Jerome Johnson.
These embittered partners became Left-Winger and Right-Winger, revealing Walker's true identity to the public in Captain America #341, by Mark Gruenwald and Kieron Dwyer. As a result of Peter's fame and glory, he inadvertently allowed his Uncle Ben to die at the hands of the same burglar who he let go. By comparison, Walker's public identity resulted in the death of his parents, who were killed by the Watchdogs.
Walker wasn't as responsible for his parents' deaths as Peter was for Uncle Ben's, but it was his newfound fame and broken relationships which led to their demise. For a time, both men externalized their losses. Peter angrily went after Uncle Ben's killer, while Walker became even more unhinged than before. The key distinction, however, is how the two heroes were stopped.
Peter realized that Uncle Ben's death was partially his fault, replacing his rage with guilt. Walker, on the other hand, ultimately had to be taken in by Steve Rogers, the original Captain America, in Captain America #350, by Mark Gruenwald and Kieron Dwyer. Later on, both heroes began acting out of a sense of responsibility. These responsibilities manifested in different ways.
As Spider-Man, Peter vowed never to let another criminal escape his watch. As US Agent, Walker decided to dutifully serve his country and his government. John eventually became an Avenger, with his responsibility manifesting into a life of service. US Agent may not have ended up like Spider-Man, but their origins hold some surprising similarities.