Settings for the font in .vimrc are not working

Following the answers in I have tried many varieties of setting the font size and face in ~/.vimrc . None of them have any effect

set guifont=Menlo:h12

set guifont=Monaco:h12

set guifont=Menlo Regular:h12

Note that executing

:set gfn=*

does bring up a font chooser dialog – and I am able to choose either Monaco or Menlo or many others correctly. But I don’t want to have to choose every time – thus the ~/.vimrc . What might be wrong how to fix this?