> So if you show your fist to a child or to Mike Tyson it's the same threat?

Based on the meaning of the word threat, yes.

No. Think forward and imagine you escalate on the threat, by punching your interlocutor. Your act is the same in both cases, but the physical injury to Mike Tyson will likely be minimal whereas that inflicted upon the child would be significant, perhaps even severe. To say they were the same would be like considering two similar mathematical operations to be equivalent without considering the quantities involved.

Emotional injury would also occur, the child is growing and would interpret the act drastically differently than a world champion boxer

Thats risk. The threat is the potential action. The risk is the potential for loss or impact.

If I showed my fist to Mike Tyson, he's pretty likely to guess that I would fail miserably if I tried to follow through, and I'd be the one who ended up getting punched...and he'd be right. It's not crazy for the legal system to take that into account.