I have always thought that Rogers And Hammerstein hit the nail on the  
head in "You've Got to be Taught" from South Pacific which goes :

You’ve got to be taught to hate and fear,
You’ve got to be taught from year to year,
It’s got to be drummed in your dear little ear—
You’ve got to be carefully taught

You’ve got to be taught to be afraid
Of people whose eyes are oddly made,
And people whose skin is a different shade—
You’ve got to be carefully taught.

You’ve got to be taught before it’s too late—
Before you are six or seven or eight,
To hate all the people your relatives hate—
You’ve got to be carefully taught!
You’ve got to be carefully taught!

Or the Merry Minuet (Sheldon Harnick) which comes with a variety of  
lyrics that are changed to suit what is going on in the world at the  
time. This version is by the Kingston Trio.

They're rioting in Africa. They're starving in Spain. There's  
hurricanes in Florida and Texas needs rain.
The whole world is festering with unhappy souls. The French hate the  
Germans. The Germans hate the Poles.
Italians hate Yugoslavs. South Africans hate the Dutch and I don't  
like anybody very much!
But we can be tranquil and thankful and proud for man's been endowed  
with a mushroom shaped cloud.
And we know for certain that some lovely day someone will set the  
spark off and we will all be blown away.
They're rioting in Africa. There's strife in Iran. What nature  
doesn't do to us will be done by our fellow man.

James Brothers, RPA
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