I'm sure there was a diversity of responses, but I'm curious if other nations had trouble understanding why it was even an issue.
BackStory (an awesome US history podcast) addressed this in their show about the Civil Rights Act of 1964. LBJ's work on the Civil Rights Act was very much shaped by the Cold War, as segregation was some seriously bad PR for the US, especially when diplomats from African countries in the process of aligning with the US or the USSR were forbidden from eating at lunch counters on their way to DC. This was certainly an embarrassment for the US, but on the bright side this embarrassment sped up the process of reform.
Source:http://backstoryradio.org/shows/legislation-impossible-2/