Why is there no EM radiation emitted in direction of travel of charged particle?

Just using an antenna as an example. Considering a typical half wave dipole antenna, all of the radiation is in the broad side (perpendicular to the direction of travel of the accelerated electrons.) As far as I've learned, there is no EM radiation emitted that is parallel and in the same plane as the moving electrons. Why is that?

Is it because the magnetic fields are created perpendicular to the direction of electron travel? (That fact not being reducible to any sorts of "why" questions?)

hi,
The Faraday Right hand rule covers this point.
https://en.wikipedia.org/wiki/Fleming's_left-hand_rule_for_motors