I do agree with you that US success in the 19th century was due to many factors that are not relevant today.
it was not "available", it only became "available" after we killed off nearly all the inhabitants and stole their land
The Indians were nomadic hunter-gatherers who were sparsely distributed around the US and moved seasonally. Diseases killed the majority. Inter-tribal warfare was the second leading cause of death (tribes that had been fighting for generations with rocks and sticks got access to horses, steel blades and guns and became much more lethal) and deaths attributable to European settlers were negligible compared to the first two causes.
yes, diseases killed the majority, but the diseases didn't come out of nowhere, they came from the European occupiers. and inter-tribal warfare killed plenty. but we're talking about theft of "available" land: the Europeans took the land from the remaining inhabitants, killing those who resisted, and deceiving those who submitted through treaties which they repeatedly broke, leaving the natives, by design, with the worst, most infertile land in the country
don't try to gloss it over and hand-wave it away -- yes, the natives were greatly diminished through the causes you mentioned, I never said the European occupiers killed them all, but it was genocide to finish them off and take all the land from anyone who resisted, effectively destroying their civilization
and stop calling them "settlers", they did not "settle" the land, they took it by force and deception
(You'll probably want to avoid metrics like happiness indices and life expectancy though)
(Or at least, people wanted to come until the last couple of years...)
Obviously you can also say that the US is geopolitically successful because of its global military and diplomatic dominance, but I account zero value to this.
There's also proportion of adult in prisons, people who believe in angels, and the mass-shooting high score
> AC units per capita
This gave me a laugh
People migrate for economic opportunity. South Africa is not a rich country, but sees millions come in from the SADC for this reason, despite some pretty big social problems.
The US is nothing special, it's just a particularly large market of economic opportunity with a history of allowing in migrants. If China was significantly more migrant friendly, we'd see the same happen there. None of this specifies that the US has some secret recipe for success that papers over some of its obvious and glaring deficits.