""left wing nationalists"?."
Ewan was an internationalist, as I believe most socialists are, (I certainly am) or at least not hostile to other races or cultures
If you are familiar with 'The Song Carriers' (worth getting to be if you are not) he made a point of showing the similarities of singing internationally using first an Azerbajan singer and Irish singer Paddy Tunney, then a Spanish Canto Hondo singer and Street singer, Margaret Barry
MacColl's take on singing in your own tradition had to do with the fact that British singing Traditions are "word based" rather than musical performances
Having said that, Ewan's finest composed song (IMO), Joy of Living was set to a Sicilian traditional tune
Education-intelligence - the former is the information you receive - the latter is your ability you interpret it      
Let's face it, our world is run by educated morons who have bought their education - I can think fwo world leaders without breaking step
Jim