@MeAgainAgain
I wasn't seeking to justify harassment which seem to be the majority of examples in your post:
"including the ones who overstep." - If a mark is overstepped then it's harassment (subjective of course)
The issue for me is that many men are extremely persistent and get angry if you don't give a reaction that they approve of. - I would certainly dispute the 'many' but persistence and anger in the face of rejection is also harassment so I'd agree.
Harassment can certainly include words. Words that men shout at us all too often.
Again, I agree with you, in fact I would suggest that shouting at anyone is harassment.
Women and girls do approach men they don't know and start chatting them up, but it's much less common.
Again I'd dispute that it's MUCH less common but that's not the point.
Yes, persistence, aggression, crudeness, shouting, cat-calling etc. are quite right to be described as harassment (agree with you definition of unsolicited physical contact too).
My point was that if we classify smiling at someone and small talk as 'harassment' (when it isn't accompanied by any of the factors listed above) then aren't we just making human interaction between the sexes a minefield that is virtually impossible to navigate?