Richard Clark wrote:

Half wave antenna can be a monopole however the reverse is
can only be true if its resonanance is at 1/2 wave.

...
Richard Clark, KB7QHC

Richard:

I think he means a half-wave monopole is quite possible (I use 'em all
the time!), and a half-wave dipole can exist with each leg being 1/4
wave ... both (having in common) being a half-wave antenna.

Or, at least, that is the way I read it ...

Regards,
JS