I can't completely agree with you. Obviously the US isn't doing that well in its fight against the COVID 19 epidemic, and Trump is responsible for most of it. At least during the initial days, he downplayed the pandemic and refused to take the precautions. The lockdown was only announced after a lot of lives were lost and millions got infected. But that has nothing to do with the foreign policy.
I agree that Trump's Covid-19 response has little to do with foreign policy, other than leaving the WHO and the public relations fallout of decisions such as that to
buy the complete global supply of remdesivir.
But many of his other decisions point to America turning its back on the world and focusing inwards, which is not what is required in a global leader. For all his belligerent posturing, he is no interventionist throwing troops in everywhere and asserting an American presence. As another example, he pulled out of Syria.
For Trump, it's America First. A consequence of this is that it's 'rest of the world last', which means relinquishing that position as the global leader. The question is does this open the door for China?
Trump is an indecent human being, an abomination. I wish there were more honorable conservatives to take his place. His viewpoint on the western allies feeding off of America is a very rudimentary, layman's viewpoint that resonates with a lot of the populace. The underlying explanations on how these "investments" safeguard the world for American trade, American corporations and allowing America to retain its position is much more difficult to understand than, "I give more money to NATO or WHO, I want money back". This indeed led to a few ruffled feathers and a re-organization of the world order seemed very much inline.
Fortuitously, the Chinese threat rose at almost the right time for US leadership to realize these blunders. Reacting to China has been high on Trump's agenda and he did not miss the chance to do so in the case of recent Chinese aggression at Indian border. China had been playing games for a long time at the SEA-Pacific ocean (Taking cue from @STT and not gonna call it South China Sea). The land based aggression at Indian border probably proved to be the tipping point. This is important because it seems the US leadership is not in the mood to let China become the new Russia (Remember Crimea!!).
The door has long been open for China. It remains to be seen what happens when China takes the crown of prime ideological aggressor from Russia. Meanwhile,
China seems to be sending warning to the US Navy in the "South-East Asia-Pacific Ocean" or SEA-Pacific Ocean.