On January 1, 1979, China and the U.S. established diplomatic ties. After nearly four decades of ups and downs, the relationship between the world's two largest economies has come to a crucial moment.

Cooperation or competition? Partners or enemies? What defines the relationship? What should be the nature of the relations?

 American political scientist Graham Allison has caught the world's attention for coining the term "Thucydides Trap," which refers to the situation when a rising power causes fear in an established power, which escalates towards war.

However, he claimed that the Thucydides Trap is something both countries could avoid... by doing the right things.

Earlier this month, Chinese President Xi Jinping and U.S. President Donald Trump agreed to a 90-day reprieve from a war of tariffs, but what could happen next? On the sidelines of the "Understanding China" Conference, Tian Wei sat down with Professor Allison for his insights.

In the interview, Professor Allison named a few words that often mentioned in the so-called decoupling idea: new Cold War, decoupling and isolated. According to him, people are just talking these words, and it is not likely to happen.

 China now is a backbone of the global economy and the major trade partner of every American ally and friend in Asia.

 "If you go to Australia or to Singapore or to Japan and you say I have a good idea, you should decouple your economy to be friendly with us from China, they don't know what you are talking about, they say do you know China is our major trading partner, China is a central for economic growth, if my government would do that and have a economic recession, I won't be the leader of the government, so this not going to happen. " said Professor Allison.

Sometimes people are imagining that they could decouple China the way the U.S. did to the Soviet Union in the Cold War. Professor Allison holds different idea, according to him, the situation is different now.

In 1950, when the U.S. adopted the Cold War strategy to isolate Soviet Union economically, Soviet Union was 10 percent the size of U.S. economy, and US was 50 percent of the global economy.

However, in 2018, China is slightly bigger than U.S. economy, and U.S. is 14 percent of global economy.

"In 1950, the Soviet Union was autarkic economy that only traded with other communist countries, they didn't have trade with anybody, and China is now the major trading partner of every American ally and friend," added Professor Allison.