This is a short-term solution to the problem. However, Israel has many other constitutional problems that make a permanent resolution problematic. They will be discussed in the next section.
Israeli soldiers should be given a choice of whether or not to protect the settlements. A soldier may decide against protecting the settlements at any time. This is in accordance with the fact that no-one can force a different person to protect someone.
Those soldiers who will opt out of protecting the settlements will serve in the territorial Israel exclusively.
The settlements can either remain using only their own self-protection and that of the soldiers who are willing to protect them, or its settlers can choose to relocate to Israel, where they be given alternative homes. (as their right as Israeli citizens)
Preferably: stop giving relief to the Palestinians. If it implies establishing a Palestinian state, so be it.
That way, the Israelis will no longer need to support the settlements, which are a huge waste of resources, and can safely exit out of the settlements. Protecting Israel against attacks would be easier from within the territorial Israel, without having to protect tens of settlements and their inhabitants.