But the Tokyo Olympics has allowed athletes from both countries to demonstrate what their governments haven't for years: friendship.
On Tuesday, Chinese gymnasts Guan Chenchen and Tang Xijing won gold and silver respectively in the women's balance beam final, while US gymnastics star Simone Biles claimed bronze. Both Chinese gymnasts are first-time Olympic medalists.
The win was particularly significant for Guan as the 16-year-old identifies Biles as her hero, according to her biography on the Games' website.
After the results were announced, a beaming Biles embraced Guan. Her US teammate and all-around Olympic champion Sunisa Lee, who had loudly cheered on Guan during her routine, also hugged Guan. Afterward, Lee posted on Instagram that she was "so proud" of Guan, and retweeted a video of Guan's dismount from the beam, captioned, "I love her (so much)."
The enthusiastic celebration and the warmth exchanged between the teams — so rarely seen now as US-China relations and public sentiment sour — quickly went viral online.
"We feel the same! This is what it means," tweeted the official Chinese Olympic Committee, along with a heart emoji and a photo showing the celebration between the four athletes.
Even the nationalist Chinese tabloid Global Times chipped in, saying in an article Lee's "sincere and joyous reaction touched viewers around the world."
And many on the Chinese social media platform Weibo praised Biles and Lee for their sportsmanship, arguing the kind of camaraderie they shared with Guan and Tang embodies the true spirit of the Olympics.
"No matter where you are from, what race you belong to, what beliefs you have, people in international society should unite together, making human life better," said one Weibo user, according to state media. "I see that hope at the Olympic Games. These athletes give us a good example."
Editor's Note: A version of this story appeared in CNN's Meanwhile in China newsletter, a three-times-a-week update exploring what you need to know about the country's rise and how it impacts the world. Sign up here.
The United States' Breanna Stewart plays in a basketball semifinal against Serbia on Friday.
Once again, Team USA's women's basketball team will play in the gold medal game at the Olympics.
The American women defeated Serbia 79-59 in the semifinals Friday to reach their seventh consecutive gold medal game. They've won every gold since the Atlanta Olympics in 1996 and boast a 54-game winning streak in Olympic play that dates back to the bronze medal game in 1992.
Brittney Griner — a star in the WNBA with the Phoenix Mercury — led Team USA with 15 points and 12 rebounds. The Americans will await the winner of Japan and France, who will play later Friday in the second semifinal.
The gold medal game will be held Sunday in Tokyo. Should the US win, WNBA stars Sue Bird of the Seattle Storm and Diana Taurasi, Griner's Mercury teammate, will become the first athletes to win five gold medals in any team sport in Olympic history.