It's also the case that employers in higher education in the UK and many other countries did not constitute a monolithic block. I know of two cases where objections were made to the appointment of British communists / ex communists on a political basis in the 1980s; one for a post in Canada, the other in continental Europe. In both cases democratic processes in the respective universities rejected these objections and the appointments were confirmed. One of the individuals was a Euro, the other was of a different persuasion. During the cold war the state was able to get people sacked from universities for their politics; by the 60s this was much, much more difficult in the UK. Incidentally, the father of one of the Euros named by PK was sacked from an engineering job in the 1950s because his company signed a contract with a US company that specified that no communist should be employed by the UK company. He retrained as a teacher.