Love it Phizzy !!
Unfortunately that smugness has an effect and for years I came across arrogant but may not have realised, well sometimes I did but that was probably on purpose ha, but I'm just referring to the in built smugness/arrogance that is inculcated from childhood.
When your dumb-dumbed like that for so long into believing you are the only right or true people on the entire planet ( yes that sounds crazy ) I think you intuitively become smug and that is oh so sad and destructive.