Team USA’s swimming dominance continues. And so do its rivalries.

Team USA swimming is not different from other high-profile Olympic team sports: Its dominance has helped push the world to get better. Names like Phelps, Ledecky, and Spitz point to America’s historic might.

As always, that dominance sets a high standard – and prompts the equivalent of a geopolitical battle for supremacy in the pool. This Olympics, that has been on full display, particularly among America; its traditional top rival, Australia; and relative newcomer China.

Former Australian swimmer Cate Campbell, who failed to qualify for the Paris Games, sparked the latest back-and-forth trash talk prior to the Olympics. She called swimmers from the United States sore losers and complained about having to listen to “The Star-Spangled Banner” every time the country wins gold.

In the pool, the rivalry hit a high point in these Olympics at the highly anticipated women’s 400 freestyle, where Australian Ariarne Titmus won and Katie Ledecky finished third. The same night, the U.S. took silver in the women’s 4x100 freestyle relay. Australia took gold, while China took bronze.

There is a clear skepticism poolside when it comes to the Chinese swimmers. Twenty-three Chinese swimmers (including some who won gold in Tokyo) were found to have used performance-enhancing drugs. Eleven of those swimmers are competing in Paris.

“I hope that everyone here is going to be competing clean this week,” Ms. Ledecky said before competition began. “But what really matters also is, were they training clean?” 

Members of the U.S. team say they were prepared for the rivalries – new and old.

“There’s always the internal fire,” says team member Abbey Weitzeil. “We’re very competitive people, and I think it brings it out a little bit.” 

That competitive fire roared on swimming’s opening night, when Team USA kicked into a gear no other team could match halfway through the men’s 4x100 freestyle relay. Team USA’s first two swimmers, Jack Alexy and Chris Guiliano, stayed neck and neck with the competition. Then Hunter Armstrong jumped in the pool and pushed himself ahead of the field with arm pulls that looked like he had the power to move water from in front of him with the wave of a hand. Yet the crowd at Paris La Défense Arena reached its crescendo when Caeleb Dressel shot into the pool like a speedboat, chopping his way to the finish more than a second faster than silver medalist Australia. 

It was the third straight Olympics that the U.S. men had won this race, and the first American gold medal at these Games. Night 2 saw Americans Torri Huske and Gretchen Walsh win gold and silver with China’s Zhang Yufei taking bronze. On Night 3, the U.S. racked up four silver and bronze medals.

It would seem as if collecting shiny medals is Team USA’s raison d’être. Team members and coaches say pushing for excellence is the identity of the program. 

Ms. Ledecky attests to that. She was 15 years old when she made her Olympic debut in 2012 and spent much of her first year with the team soaking up advice from the veterans. Twelve years later, she’s the veteran with 11 medals, including seven golds. Yet to come in this Olympics are the 800 and 1,500 freestyle, races she excels in. Yet while racking up medals, she hasn’t missed the chance to learn lessons along the way.

“Competing at this level has taught me a lot,” Ms. Ledecky recalled before the competition started.

“The biggest thing that I’m thankful for in the sport is the people that I get to share these experiences with and the friendships,” she says. 

And frankly, the rivalries are part of that catalog of Olympic memories and people.

“That’s what’s so special about the Olympics,” she adds, “how it brings athletes together from all over the world, all different sports, and you get to meet some phenomenal people and build friendships.”

How do athletes cope with the pressure of competition? Find out more: They stepped away for mental health. Their comebacks are powering the Olympics.