Sorry about the above

According to the Guardian article article Abel took the pseudonym Lewis Allan after his two sons who who were both stillborn.

As a communist teacher in New York in the 1930s Abel would have been vulnerable to be sacked and as a Jewish person he would have been vulnerable to attack from right wing racists.

The Palmer Raids of the 1920 s had meant a witch hunt of communists and leftwingers and I think Abel would have felt exposed as the fame of the song spread beyond trade union and progressive circles.
Albert