Nice thoughtful post there AJ. One thing, with the formation of Malaysia from several British colonies, there was going to be a big Malay majority. Singapore, being a majority Chinese city was not happy with that prospect and some wanted out. They were not thrown out as I remember. I did some work in Terengganu in Malaysia several years later and I did see the Malays strongly favoured over ethnic Chinese and Indians. Looked to me that Singapore made the smart decision. While Singapore was a success story, Lebanon was the opposite. Christian Lebanon, like Singapore was a financial hub, they had strong institutions, universities, hospitals and a beautiful city in Beirut. Great social life. Arabs used to bank and play there, send their children to higher education there. Then there was the power shift as Muslims took control and now look at it. I remember the Holiday Inn and the Venetia hotels were regarded with pride by locals, but a few years later I saw them in newsreels with holes blown in them In a smaller way that was like Gaza. They had successful farmers and a thriving greenhouse industry producing all sorts of fruit and vegetables. Then Israeli farmers were forced off their lands in the Gaza Strip. After Hamas took over the greenhouse industry all but vanished. I don't know the details, but I rather suspect it is systems of govt that make the difference, more than ethnicity or religion.
