Second place for Sebastian Vettel has put the Red Bull driver on the verge of a third consecutive title at the championship decider in Brazil next weekend.
Hamilton claimed the lead from Vettel – who had been quickest in every session – in the closing stages of the race, with both the drivers having fought each other hard from start to finish.
Hamilton and Vettel used the same strategy, stopping just once to change from the P Zero White medium tyres to the P Zero Silver hard tyres (the two compounds nominated for the United States Grand Prix) on laps 20 and 21 respectively.
Alonso opted for an identical strategy to keep his title hopes alive, having started from sixth on the grid to move up to third.
All of the top 10 qualified on the medium compound, which was around half a second per lap faster than the hard tyre, on one of the fastest-evolving tracks seen all season because of its freshly-laid asphalt.
The possibility of rain that had been predicted earlier did not materialise, with ambient temperatures in the region of 24 degrees centigrade, setting up a flat-out race to the chequered flag on the brand new track.
The highest-placed competitor to start on the hard tyre was McLaren’s Jenson Button, who eventually finished fifth thanks to a one-stop strategy. Mercedes driver Nico Rosberg was the only other driver to begin the race on the P Zero Silver.
Pirelli’s motorsport director Paul Hembery concluded: “We’d like to thank all the fans who came in their hundreds of thousands to Austin this weekend: the level of support and the welcome we received has been unbelievable and we can’t wait to come back.
Both the championship protagonists, Sebastian Vettel and Fernando Alonso, drove magnificently today and the result is going to be a thrilling championship showdown in Brazil next weekend.
Although in retrospect we could have come here with even the soft and the supersoft compounds, the fact that the title battle is now going down to the final round reinforces our decision not to introduce any unknown factors at a brand new circuit, where the title battle was so finely balanced.
Levels of degradation were extremely low throughout the weekend, although this was also affected by ambient and track temperatures that were generally lower than expected.
Performance and durability were extremely good on both compounds, allowing Vettel and Hamilton to race each other all the way to the flag.”