Think back to your own primary school experience and ask yourself: do you ever remember your teacher being hit by a pupil? The likely answer is that it absolutely never happened. Now ask yourself if one of your colleagues was struck by a child in the last few years.
Violence (physical and verbal) towards adults in schools is starting to become the norm in many schools. While a lot of it is done by very small children, it is a worrying trend. It also needs to stop.
There is absolutely no reason why a child should be allowed to harm another adult in the school.
My suggestion is that there is an overall acceptance of this fact and that no parent will be surprised to get a phone call to collect their child immediately after an assault, followed by a suspension. While I absolutely understand there may be children with additional needs that cannot control this, interventions would also need to be put in place to minimise the risk of violence towards adults caring for the child.