About 20 years ago I had just retired from being a Playgroup supervisor. Our Branch of the PPA used to put on a puppet show every year and many of the local groups hired coaches and took children to one of the performances. I joined the team for a few years.
One of the puppets who turned up every year was a naughty monkey. And one particular script included this song - I said I didn't think it was appropriate, but was over-ruled. The whole theme of that script was dodgy, I thought - monkey goes in a space rocket, lands on mars and meets funny green men, lands in the USA and meets funny red men. The puppet show had been going for years and the scripts reused.
Things do change - slowly. Back in the 40's when we sang 'little brown children' in Sunday school there weren't many brown or black people in England.