Forty-nine years ago today, on April 6, China extended an invitation to a table tennis team from the United States, who was in Japan for a championship, to visit the country. The world was shocked. It was, after all, at the height of the Cold War.

This is the acclaimed "Ping-pong Diplomacy" that led to US President Richard Nixon's visit to China in 1972 and helped thaw the 20-year freeze between the People's Republic of China and the United States.

Despite ups and downs in the following four decades, the China-US relationship is still widely believed to be the single most important bilateral relationship of the 21st century.

However, with the whole world at the mercy of the COVID-19 today, the engagement between the two nations has been disappointing, if not costly.

Faced with the fact the United States leads the world in confirmed cases of the COVID-19, the Trump administration, from its most recognizable faces to little-known officials, seems to be busy with the business of passing the buck to China, which first reported the outbreak back in January, but has generally contained it since early March.

Their mentality and words go like this: We botched our initial response to the pandemic, because China covered it up; because China didn't warn us enough; because China expelled our reporters so that they can't report about it; because it was the "Chinese virus," and because China…you name it.

As recently, when China, having stand on its own feet, is able to supply other coronavirus-stricken nations with desperately-needed masks, ventilators and other personal protective equipment that save lives, it didn't take long for some in Washington DC to accuse China of turning the pandemic into a geopolitical weapon.

At regular briefings and on Twitter, the Chinese Foreign Ministry spokesperson has already spent minute after minute debunking these poorly-founded accusations.

But sadly, some officials of the United States have chosen to turn a deaf ear. Luckily, the American people are different from them.

Some US teachers are posting on social media the photos of packages of masks their students in China have sent them, along with emojis of hearts and thanks. The Chinese parents said the gesture was just a favor returned, since these very U.S. teachers were sending them masks from overseas at the outset of the outbreak in China.

This kind of people-to-people exchanges of the two countries can, and should be the new ping-pong diplomacy that ushers in another era of cooperation between China and the United States.

The reasons? As every single person on this earth has probably already known, the virus respects no borders, or discriminates any nationalities, nor can it be swayed by the Thucydides trap, the talk of decoupling, the trade war or the tech war, let alone a war of words.

Given its nature, the virus actually offers a silver lining: a once-in-a-lifetime opportunity to rethink the relationship between the world's largest economy and the second-largest economy. Here is a hint: the virus does not play a zero-sum game, neither it thinks in that way.

When Nixon was in China in 1972, he said the world was watching what China and the United States would do next. He cited a poem by Chairman Mao, "ten thousand years are too long. Seize the day, seize the hour," before he added his own comment, "This is the hour. This is the day."

This is the day for China and the United States to "rise to the heights of greatness" to fight the common enemy of humanity: COVID-19. The world is watching again.