What makes America great is everything we used to have. American morals, values, pride and standards.
There is a reason why America is a very young country and we rose to the top of the food chain very very fast. We went from nothing to a world super power because of our pride, values, morals and standards. Other countries both feared and respected us.
It also helped Americans also in general spoke the same language, had the same culture, the same religion, the same societal norms and so on. It made us all be able to band together because we all were similar to each other. Those commonalities united us. It's why even a common worker had a home, a car, took a vacation every year, always had plenty of food.
Even politicians still had a common goal of what's best for America as a whole. Even misguided, both parties were still about america first.