The Wallabies opened the scoring after seven and a half minutes, when Rob Horne crashed over in the corner after he found himself on the end of a Kurtley Beale pass.
Beale added a try of his own after 30 minutes, but was substituted shortly after by Berrick Barnes, with a suspected leg injury.
In between jinking and jiving his way around the paddock, Quade Cooper produced some moments of class for Australia, although his goal-kicking will have left Deans with a headache.
The Queenslander kicked two from five in an unconvincing display with the boot, although if anything it saved the Americans further disappointment in terms of the scoreboard.
Barnes took over the kicking duties for the majority of the second spell and sunk his first attempt from the sideline.
More than 33,000 people packed in to Wellington Regional Stadium and many a chant of "USA, USA" erupted throughout the game, but when the Mexican Wave took off only 15 minutes in to the fixture you got the impression the crowd were there to enjoy their hot dogs and beer as much as the rugby.
The United States also enjoyed 59 per cent of possession in the opening stanza and a 54 per cent territorial advantage, but they couldn't turn it in to enough points.
Brumbies flyer Adam Ashley-Cooper came in to the game in a big way during the second half as he bagged a hat-trick in seven minutes and three seconds, which is sure to become some sort of Rugby World Cup trivia question.
Between the 59th and 66th minutes the 98kg winger found himself on the end of the chain, after he barely touched the ball in the opening spell.
As the second half wore on, the Australians, who had a point to prove after their shock loss to Ireland last weekend, found more and more gaps in the United States' defence, which they exploited to great effect.
Replacement back Pat McCabe went off the field with a hand injury, which forced giant back-rower Radike Samo to play out on the right wing for the final quarter of the game.
The 1.95m makeshift outside even found his way over the chalk for a popular try late in the match.
Centre Anthony Faiangaa suffered a scare when he was taken off the park on a stretcher, just before full time.
Australia 67 (Adam Ashley-Cooper 3, Anthony Faiangaa, Rob Horne, Rocky Elsom, Kurtley Beale, Drew Mitchell, Pat McCabe, Radike Samo tries; Quade Cooper 2 cons, Berrick Barnes 4 cons) United States 5 (JJ Gagiano ) HT: 22-5