So it depends what you mean by 'best'.
In most developed countries, if your situation is ideal you can get fantastic healthcare, and that seems to be the point you are making.
There are some niche fields where the USA is demonstrably the best - pediatric oncology surgery, some difficult transplants, and novel cancer therapies come to mind. But I think it is hard to argue that it is anywhere near the best on the metrics usually used to judge a healthcare system, which other people have posted about.
In my experience, it also suffers from thinking it is the best and patients expecting it to be best. I have seen some patients get quite excessive and even unusual treatment in hallowed healthcare institutions in the USA.
There are some niche fields where the USA is demonstrably the best - pediatric oncology surgery, some difficult transplants, and novel cancer therapies come to mind. But I think it is hard to argue that it is anywhere near the best on the metrics usually used to judge a healthcare system, which other people have posted about.
In my experience, it also suffers from thinking it is the best and patients expecting it to be best. I have seen some patients get quite excessive and even unusual treatment in hallowed healthcare institutions in the USA.