Not sure about superiority but it existed. We have 0 moral code today, that is the issue.
The key moral issue that I think impacts the USA is the lack of focus on family. I think the free love movement was the biggest disaster for our nation because it led to children being raised in horrible homes, no homes at all, or single-parent homes.
The two-parent, nuclear family is tied to historical success of Civilization. The push by Elites to get away from that is running our nation into the ground. It is especially harmful for minority and low-income families.
It is clear with the plummeting birth rates, increase in suicides, the constant difficult in dating/marriage (high divorce rate, incel movements, women's issues with increasing suicide, etc.), the higher crime rates, etc. that the decline of the family is causing a lot of issues.
Biggest issue is that EVERY CHILD deserves a safe home to be raised and we don't have that.
It wasn't perfect in the past either but it was stronger than today.
People also see a United States in the 1800s that expanded from East Coast to control North American Continent, went from backwater economy to the #1 Economy in the Globe by 1920, that won every war in the 1800s besides the war of 1812 (notably the successes of the Mexican-American and Spanish-American wars; USA would not win those type of wars today), freed the slaves/ended slavery, tamed the Wild West, built wonders like Mount Rushmore, steered us successfully through two World Wars, invented most of the modern technologies we have today that have made our life better, and had an educated system that eventually created the Scientists that invented the Atom Bomb, took us to the Atomic Age, and landed a man on the moon.
The 1800s and early 20th Century was very good for the United States. You can't argue with results.
If our Civilization was on track, we would have colonized the Moon and Mars by now, have raised more people out of poverty, wouldn't be $ 33 Trillion in debt, and would have flying cars (see Back to the Future II lol). Instead, our Civilization advancement has slowed dramatically, our education system is a mess despite having more money, staff, and regulations than ever, and our military/global influence is in decline.
I feel like the corruption and regulation brought by our government today is getting on par with the same systems that ran the USSR into the ground and has kept Latin American nations from becoming players on the Global Sphere (Brazil is one of the greatest enigmas in history because with the land area, population, education, and resources that Brazil possess, they should be one of the major global powers but they have almost 0 impact in the Global/Political sphere).