As predicted, US President Joe Biden took advantage of the G7 Summit and the Munich Security Conference on Friday to announce that "America is back".

But neither the United States nor the world is the same as they were four years ago, when the world had little knowledge of the extent to which a so-called champion of democracy and freedom could belie itself.

That being said, Biden sought to draw a clear distinction between his administration and that of the "former guy". Any slight reluctance to do so would have been perceived by his audience, and he would have been given short shrift. That's why he tried to calibrate his speeches at the back-to-back meetings to make sure they coupled well with his audiences' expectations.

But despite the nods of welcome the US received on announcing its return from the wilderness, the US leader should be well aware that he is still out of step when it comes to China.

As the speeches of European leaders indicate, the US should not come back to the international fold for the purpose of joining hands with its allies to contain China. It should come back to join hands with the rest of the world to try and meet the acute challenges humanity faces.

As one of the largest traders, outbound investors, manufacturers and destinations for foreign investment, and a major advocate of fairer global governance and common development, and as the largest contributor to world growth and largest contributor of essential medical supplies to the world's fight against the COVID-19 pandemic, China is the touchstone to tell whether the US has come back wiser or whether it will persist with its folly.

If it has come back to try and rally its allies under its banner to contain China, what is back is not America, but just a lesser version of the country's former administration.

And if that is the case, then the welcome it has received may prove short-lived.

While the Biden administration sees China as "the most critical competitor" of the US, most leaders in Europe and beyond see China as a partner with whom to work for the common good.

What has happened over the past four years should be enough to prove that any efforts to try and isolate China are doomed to fail. And if as he says, he has greater insight into the most important bilateral ties in the world and a deeper understanding of the importance of China policies, Biden should recognize that even as its ties with the US became increasingly strained, China has maintained its composure, openness and commitment to cooperation.

His administration should act decisively and sweep the waste of its predecessors' policies into the dustbin of history.

It's time the US moved on.