The situation on the ground has changed.
I am morally against it. But if terrorist acts - and I mean ACTS are performed (as defined by life threatening acts against people because of their ethnic identity) then sure - expel THAT person - not the family, not the tribe, not anyone else. Or - put them through the criminal justice system. Actually that might be better.
But it has to be applied equally - that means Jews committing acts of violence against Palestinians should get the same treatment.
What I'm afraid of though is that this will be abused and used as a reason for mass expulsions much the way demoliting the family homes of Palestinians is abused as a group punishment.
How can such abuse be prevented?
So, here's the thing. Such "abuse" can be prevented by
Arabs refraining from being hostile and committing acts of terrorism. Full stop.
In a one state solution, Israel will have a significant minority of Arab citizens who are hostile to Israel and to Israel's Jewish citizens. Any hostilities, overt, covert, incitement, actual acts of harm or terrorism are the responsibility of those committing the violations. Full stop.
The question being asked here is not, "How can we prevent Israel from abusing Arabs?" The question is, "In the face of a hostile and violent minority population, how should Israel respond to acts of violence, threats of violence and a culture of violence and hostility?"
Is the answer expulsion? Its a bigger question than just "what to do with individuals who commit acts of terror". Its a question of managing that hostile culture.