It's not the USA, Russia, nor China; the most successful Tokyo 2020 nation is... San Marino!

1

X

2

1

X

2

1

X

2

1

X

2

1

X

2

1

X

2

1

X

2

1

X

2

1

X

2

1

X

2

1

X

2

1

X

2

1

X

2

1

X

2

1

X

2

1

X

2