I’ll take a stab at it. Without trying to wish away things that can’t be wished for.

Transition the administration of the contested area (mandatory Palestine basically) over to a secular representative government. With peacekeeping provided by the UN. The secular government should be completely separate from any religion, but have the right to religion as part of the Constitution.

Encourage massive economic integration between the different ethnic populations. There will be civil turmoil for quite a while, but we’re winning slowly, demonstrating the people the future is better together. It’ll probably take two or three generations until things settle down. So we’re looking at an occupying force for 40 to 60 years.

To add legitimacy to this government, they should have a truth and reconciliation panel covering and forgiving all of the crimes of the past, they should objectively, and harshly come down on any land crimes, hate crimes, religious persecution, religious exclusion, that happens inside the country.