A melting pot vs a bowl of salad

Suppose you're cooking a cheese dip. You put all kinds of cheese in the pot: American cheese, Swiss cheese, white cheese...the more the better. Then you turn on the heat and cause all those cheese to melt and all blend together, making a rich and yummy mixture. When you dip you bread or chip or whatever you have in this mixture, you can't tell which cheese is which, as you have stripped off the particular characteristics of those cheese; all you have now is a combination of cheese: your cheese dip, in a pot.

Now you are making a different thing, a bowl of salad. You put all the ingredients together: lettuce, tomatoes, onions, green peppers, strawberries, bacon...Then you put dressing on it and taste it. All those things together gives you a different taste than each of them would give you separately, but you still can tell which one is lettuce, which one is onion, green pepper and so on. These ingredients still reserve their particular characteristics, although they're unified as one.

American immigrants have to accustom themselves to the American "new" life, but they don't discard their home country "old" lifestyles. And some American don't accept those immigrants anyway. So practically, I think America is not a melting pot; it's a bowl of salad.