My parents live in Pennsylvania and belong to several social clubs. These clubs are loosely based upon their ethnic group. The only diversity the clubs have is based on the fact that some members are foreign born while others are American born members of the same ethnic group. In that town, as in most, there is a club for nearly every ethnic group. For simplicity and to avoid prejudicing the reader I will refer to my parents' club as the Old White Folks Club (OWFC). Most of the clubs that my parents visit have a shrinking membership because they failed to attract younger people.
One evening a few young Colombians entered the club while the members were having a good time. The Colombians asked if they could sit down and have a beer. They were politely told that they could not because only members of a certain ethnic group are allowed in. However strong ethnic affiliations may be, economics is also a strong factor. Before the Colombians could leave a member of the OWFC quickly offered to rent the facility to the Colombians when the Whites would not use it. The Colombians accepted and over time a relationship grew between the two groups.
After several years that OWFC continued to lose members and the remaining people merged with a different OWFC. The Colombian group grew and was ready to buy the building. The Whites were happy to have an anxious buyer waiting.
If, on that fateful day when the Colombians first entered the OWFC, the Whites had let them in, the outcome would have been entirely different. During the first few weeks of integration everything would have gone well. Perhaps both groups would have talked and learned about each other's culture. Perhaps the Whites would have taught the Colombians how to dance to Polka music. Then the Colombians might have taught the Whites to dance to Salsa music. After a few months the Whites would feel uncomfortable as more and more Colombians came in speaking loud in a language that they did not understand, drinking tequila and dancing with a vigor that the Whites had lost decades ago. When the outnumbered Whites insist on playing a Polka song the Colombians would have certainly honored this request. The Colombians would have sat quietly watching the nervous old Whites dance while waiting for the music to end so that they could start dancing again to the music that they love. Within a few months there would be no more Whites coming and paying dues to maintain the property and there would have been feelings of hostility.
Fortunately everything worked well because the Whites had the courage to defend their right of freedom of association and the Colombians were decent enough to respect it.