Songs are songs, there is nothing that I know of in any free nation to stop someone from singing or writing anything they want. Getting someone else to listen or buy or hire you to perform is another matter entirely ... Maybe the reason Pete is so revered is that he hits a spark inside most people of the concept of right and wrong ... maybe it is also his skill as a musician and his connection to the common masses, Maybe that is why he is Pete. However, anyone else is fully free to express their voice in song also ... that does not mean that a promoter who really is in it to make a living and a profit will hire them or even listen to their music ... There is no "fair" in music business nor should there be .... It is all about quality and all about skill and all about appeal and all about staying alive financially.