Fans cheering in a stadium and waving a flag is a staple sight at any international sports event.
But what if a flag is so offensive to some countries it sparks a whole movement to get it banned?
That is what's happening with Japan's rising sun flag and the Tokyo 2020 Olympics. And the strongest criticism is from South Korea – where some politicians even compare it to the Nazi swastika.
Critics say the flag is flown by fans who want to romanticise and rewrite the human rights abuses by Japanese forces.
South Korea wants it banned at the games – but the 2020 organisers say the flag is “widely used in Japan” and is “not a political statement”.
What is the rising sun flag?
Japan's national flag is simply a red disc on a white background – and no-one has a problem with that one.
The rising sun flag has a similar red disc but with 16 red rays coming from it. Both flags have in fact been used for a long time, dating back centuries.
During the 19th Century, the rising sun symbol became the flag of the military. As such, it was flying…