“when the United States walks away from cooperative bodies — from the Paris climate accord to the WHO — it leaves behind a vacuum. China has hastened to fill it, and that, more than anything, is bolstering Beijing’s rise and influence. It gives China a chance to be a good guy — say, pledging $30 million to the WHO when the US threatened to withdraw, a fraction of the money the US provides annually. The Trump administration, in abandoning institutions for being too China-centric, is allowing them to become just that. It’s a self-fulfilling prophecy.
Again, this is not to say the US doesn’t have legitimate criticisms of the WHO, or China. But by refusing to work within the system, it is actively ceding leverage and losing credibility. Last week, in a discussion with reporters about the implications of the US leaving the WHO, Elizabeth Cousens, the president and CEO of the UN Foundation, said that even as the US is trying to push the WHO to reform, it’s “losing influence in that conversation because they’ve stepped off the field.””
https://www.vox.com/2020/9/22/21450706/united-nations-general-assembly-trump-xi