Melting Pot vs. Patchwork Quilt
The term melting pot refers to immigrants from multiple countries entering another country and the cultures “melting” together to form a new culture made up of the best aspects of each culture merged together abandoning the lesser or weaker aspects of each culture behind.
Pizza is considered a staple in America but it did not originate in America. American pizza is based on Italian flatbread dishes. Over time Italian flatbreads were altered until they became what Americans call pizza today. The Italians had created an amazing dish that Americans loved and made their own. Pizza is now as American as apple pie, which originated in England and not America either.
The term patchwork quilt refers to immigrants from multiple countries entering a new country, self-segregating or being segregated into enclaves comprised only of members of their former nationality, and operating separately as opposed to assimilating and becoming a part of the new country that they live in.
The immigrants from Franistan (a fictional nation from I Love Lucy) came to the United States and all decided settled in Columbus Ohio. They bought all of the houses in one enormous neighborhood. They continued to speak their home language, did not learn the language of the nation they lived in, bought and sold primarily to one another, and interacted almost exclusively with one another. If you went to their neighborhood you would think that you had entered Franistan and not a neighborhood in America.
They had come to America for a new and better life. However, when they got there they turned their new home into their old home and did not benefit from the positive aspects of America, and all of the nations that had contributed to it, or share the positive aspects of Franistan with their fellow Americans.