The storyline was a critical success, with praise offered for its political content, though more recent reviews have noted how its typically 1970s comic book dialogue likely reads as aged to a modern audience.

As public opinion turns against him, he discovers that the committee is a front for the Secret Empire – a splinter from the neo-Nazi terrorist group Hydra – which, under the leadership of the mysterious "Number One", seeks to discredit Captain America as part of a conspiracy to assume control of the United States government.

[5] The shift resulted in a critical and commercial reversal of fortune for the series, and six issues into Englehart's run, Captain America had become one of Marvel's top-selling titles.

[9] "Secret Empire" would ultimately conclude before Watergate was resolved,[13] though the decision to have Number One commit suicide at the story's climax was based on Englehart's belief that "the conclusion [to the scandal] seemed obvious".

[4] Englehart sought a "really shocking ending" that could lead into the subsequent storyline of Rogers' decision to give up the mantle of Captain America, stating that "Nixon didn’t blow his brains out, but he destroyed his own career and that's political suicide.

"[6] While there was frequent speculation that Englehart was pressured by Marvel into not explicitly revealing that Number One was Nixon, he stated that it was at his own discretion that the character's identity was left ambiguous, but qualified that "no one in that time and place could be unaware of my point.

[16] As a result of the events of "Secret Empire", Steve Rogers abandons the title of Captain America and adopts the superhero identity of "Nomad, the man without a country".

The writers have clearly tried to identify and articulate the feelings about patriotism and succeeding generations of Americans" and "accurately caught the changing moods of the past thirty years".

[19] Further, they noted that while the story "may be casually dismissed by elitist critics who sneer at the necessarily shallow and simplified comic book genre [...] it is fair to say that many more Americans know about Cap than about Richard Hofstadter".

[18] Mike Avila of Syfy wrote that "some elements of the story have certainly aged more gracefully than others, but it remains a great time capsule [...] of the disenchantment that permeated in large sections of America during the tail end of the Vietnam War.