Does the USA have the highest homicide rate in the world?

No. Among developed countries, we are not in the top ten, top twenty-five or even the top fifty. Try 64th (not 66th, as claimed) as acknowledged by a person originally skeptical of the claim. Here is the link. And below is the original response from the skeptic:

Here is the explanation of the source and the top seventy:

Intentional homicides per 100,000 country rankings

Date: January 4, 2023