Having defeated Jamaica earlier in the week, Gregg Berhalter's side travelled to Windsor Park full of confidence with an abundance of young talent amongst their ranks.
In fact, it also ended an 11-game away run without a win, since the American soccer stars overcame Cuba in 2016.
Niall McGinn's late goal proved to be the only mark on another successful performance by Berhalter's men, who picked up their third win of 2021 on Sunday.
The visitors started with a three-man defence, flanked by Antonee Robinson and Sergino Dest as wing-backs, for the first time since 2019 and have Giovanni Reyna and Christian Pulisic to thank for their goals.
And here's how each player got on in the friendly at Windsor Park.
Manchester City's back-up goalkeeper produced another solid performance for his country, performing his job effectively when called upon.
His most important moment of the match came just after Reyna's opener, as he dived down to his right to strongly push away Shayne Lavery's right-footed effort after a mistake from Kellyn Acosta in the middle of the park.
While not the busiest day at the office for Steffen, he made some fairly routine saves when the likes of Kyle Lafferty and Lavery evaded the away side's three-man defence.
Just like in the Jamaica game, however, the goalkeeper will be frustrated to have not recorded a clean sheet, given the lack of chances he had to deal with in the friendly.
Having barely played under Scott Parker for Fulham this season, it came as no surprise Ream looked a little rusty and at some points appeared exposed against Lavery and Lafferty.
As perhaps the weakest component of Berhalter's three centre-backs, Ream may be looking over his shoulder if the USMNT opt to return to employing just the two centre-backs next time out.
While his lack of pace represented an issue throughout the game, the centre-back did look assured in possession and even claimed the assist for Reyna's deflected opening goal.
Acting as the central operator in the middle of the visitors back three, Miazga regularly looked confident on the ball and often found the feet of Yunus Musah in midfield.
A few passes broke through Northern Ireland's defensive lines and when Miazga went long he also appeared able to create chances for the willing runners ahead of him.
The best representation of this was in the second half, when he sprayed a long pass over the top for the run of Robinson, who arguably should have done better on the left-hand side with the ball.
Despite his passing success and general composure, like Ream, Miazga's pace looked an issue and he too seemed uncomfortable with defending in the build-up to the hosts' late goal.
Recording his second consecutive appearance for the national team, Long was the pick of the centre-backs and the fact he is still only in pre-season with New York Red Bulls wasn't evident.
Long has been going slightly under the radar as part of Berhalter's camp but Sunday's performance proved why he is still rated by his manager and international peers.
A solid defensive performance was only enhanced by continuous smart passes forward and the odd cross in the first half to aid the away side's attacking cause.
If there is only room for two American centre-backs next time against Switzerland, Long should feel hard done by if he is the one to miss out on the starting 11.
As has been the case for Fulham most of the season, Robinson put in an industrious performance, although his final passes and decision making still lacks quality.
His pace proved a problem all afternoon for Matthew Kennedy but Jordan Siebatcheu was left frustrated on numerous occasions as the left wing-back's crosses were poor or misdirected.
The wing-back started the game quietly. However, he grew into it on the left-hand side and with a better range of passing, he would have guaranteed his side an extra goal or two.
Proving a threat going forward, no real problems came for him in the channel defensively as Robinson's pace and positioning often got him and his team out of any potentially dangerous scenarios.
The only slight blemish on Robinson's afternoon was a potential injury late on, courtesy of a challenge from Alistair McCann and Scott Parker will be hoping he is fit to return to Premier League action as Fulham's fight against relegation continues.
After scoring twice against Real Sociedad for Barcelona and collecting his first international goal against Jamaica, Dest put in another solid performance on the right flank.
While the 3-4-3 system was more similar to what Ronald Koeman has been playing at Barcelona, Dest was surprisingly quieter than Robinson on the other side, as the visitors seemed to prefer attacking down the left through the Fulham man.
Due to the freedom three centre-backs offered the away team, the wing-back regularly found himself operating high up the pitch and coming inside to orchestrate attacking play when possible.
Despite no standout moments, Dest performed his role efficiently and earned a well-deserved rest after his half-time removal.
Berhalter utilised Dest smartly throughout this international break and his half-time substitution only further supports the idea that the USMNT want to manage their star players' minutes.
Acosta failed to recreate his strong performance against Jamaica as he struggled on Sunday against Northern Ireland's three-man midfield.
His carelessness in possession nearly cost his team a goal in the 38th minute, if it wasn't for Steffen's smart save from Lavery's effort.
Perhaps due to still being in pre-season - as one of only two MLS players starting, alongside Long - his failure to get up to match intensity was evident throughout.
To further Acosta's midfield woes, he consistently gave possession away as he struggled to get a grip on the game in midfield.
A decent performance against Jamaica will likely keep him in Berhalter's good books but the midfielder must improve if he is to stay in the starting 11.
The 18-year-old midfielder has a claim for being the visitors' best performer, along with Reyna and Pulisic.
Making his second senior appearance, Musah is now officially an American international and his allegiances can no longer be switched.
The youngster dictated large parts of the first half, gliding past opposition players as he dominated the midfield battle as a box-to-box engine.
If it wasn't for his half-time removal - perhaps to protect his young legs - Musah could arguably have been up there for man of the match, given his impressive outing.
Appearing comfortable defensively too, the challenge for Musah will now be to consistently repeat these performances on the international stage.
Despite domestic chances for Chelsea being few and far between, Pulisic put in a captain's performance as he guided his country to another victory.
Dropping deep to receive possession or getting in behind as a runner, the playmaker was persistent and relentless in his desire to get involved.
Whether it be creating one-on-one situations or looking for his team-mates, Reyna and Siebatcheu, Pulisic's showing had it all and he deservedly topped it off with a goal.
Winning the penalty, Pulisic then duly converted it to double his team's lead before attempting to tee up Daryl Dike to cause further Northern Irish pain up top.
Pulisic's penalty also puts him on 15 goals for his country, with Landon Donovan (21) the only player to reach the landmark at a younger age for the American national team.
On another day, Pulisic could have walked away with two or three assists on top of his penalty goal as he put in a nearly complete performance for the USMNT.
Down as a right winger, Reyna was offered the freedom to ghost inside, drifting all over the place as he tormented the Northern Irish defence throughout.
Despite an incredibly quiet run of form for Borussia Dortmund, in which he hasn't recorded an attacking contribution since December, Reyna looked at ease when on the ball on Sunday.
The 18-year-old, who is the son of Claudio Reyna, got Berhalter's men off to the perfect start as he scored the opening goal past Conor Hazard - his second senior goal for his country in just his fourth outing.
Albeit via a slight deflection, the forward drilled a right-footed shot from around 25 yards out past the wrong-footed Hazard to set his team on the way to a rare European triumph.
The Dortmund man enjoyed a productive first half and a quieter second before his removal in the 63rd minute but nevertheless looked confident and caused problems for all his time on the pitch.
It is important to remember too, Reyna is only 18 and still finding his feet in the Bundesliga, all while putting in impressive performances for his country.
Siebatcheu made his first international start and lasted 60 minutes at Windsor Park, putting in a solid but not overly groundbreaking performance up top.
His hold-up play was impressive, often tasked with occupying two of Northern Ireland's three-man defence at all times.
The forward was more of an asset in defensive set-piece situations, guarding the near post form every corner, than he was in attacking situations.
By no means is this a negative on Siebatcheu's part, however, the forward was rarely granted any chances of note to challenge Hazard's goal.
The former FC Dallas right-back, who made his Serie A debut for Roma this month, came on as a half-time replacement for Dest at right wing-back.
This appearance against Northern Ireland signified Reynolds' first taste of senior international debut and the Roma man immediately looked comfortable on the big stage.
Aggressive in both defence and attack, Reynolds was unlucky not to record an assist with two smart, driven crosses across the face of goal in the second half.
An encouraging showing from the 19-year-old, however, with Dest as competition for the right-back spot, Reynolds is going to have to keep performing well for club and country to have any chance of making the position his own.
Replacing Musah at half-time, the LA Galaxy midfielder had rather big shoes to fill, given the 18-year-old's domination in the first half.
Given the nature of the second half, with it regularly stopping and starting, Lletget struggled to make the game his own and often found himself keeping it simple as his side looked to close out for the victory.
A mature performance with no real standout moments is only overshadowed due to the introduction of Musah into Berhalter's midfield options over this international break.
After being introduced in the 63rd minute, Barnsley's star forward could have grabbed a goal or two in the second half.
With Pulisic causing so many problems for the home side, Dike was offered consecutive chances but failed to beat Hazard.
The first of which, the forward saw his close-range driven effort saved by the feet of the goalkeeper before his second forced a great save at the near post.
A third opportunity came moments later but Dike missed out by an inch on a flick-on header, meaning the attacker walked away goalless from his 30-minute cameo.
Richards was also a 63rd-minute substitute but he didn't have much time to make an impact as he slotted into the visitors' three-man defence.
With not many minutes on offer, Richards will need to continue performing in the Bundesliga to earn his place in Berhalter's hotly-contested defence.
As was the case with Richards, Aaranson was part of the triple change in the 63rd minute.
The substitute always looked confident and assured in possession as he acted as a calming influence on the ball, while not contributing any significant chances further forward.
Aaronson, however, has impressed in the two fixtures over the international break so he is more than likely to stay around the national team set-up.
Luca de la Torre
Barring a smart pass in the build-up to a chance for Dike, including some lovely exchanges with Pulisic, De la Torre barely had any time to stamp his authority on the friendly.
Afforded just 17 minutes at Windsor Park, the midfielder will be looking for more opportunities when it comes to the next international break.
Next up for the USMNT is another trip to Europe to face Switzerland, who are ranked 16th in the world currently, on May 30th.