>Unlike in Mexico there was no pre-colonial, indigenous empire that had ruled and named the land which eventually became the 13 colonies.
Actually, there were multiple indigenous political entities both along the Eastern Seaboard (where we find those 13 colonies) as well as across what is now the US and Canada[0].
We just took their land and killed most of them, but they were still pretty organized -- with political groupings of various types.
Of course colonists committed genocide against indigenous people everywhere they went. No one's denying that. I'm addressing precisely what you yourself said
> there were multiple indigenous political entities both along the Eastern Seaboard
They were fragmented and smaller than the Aztec empire. That doesn't make it right to take their land. It does explain why their names didn't apply to the entire land. Because none of them was so big and centralized. If you look at the geographical features of the Eastern seaboard - mountains, lakes, streams, rivers, cities and towns, even 2 states (Massachusetts, Connecticut) - native names abound.
The lands that became the US and Canada really did have fewer people living on them than the lands that became Mexico. [1] Again because Mexico had centralized states and large-scale agriculture capable of supporting large populations.
What about Iran? Iran was conquered by muslims. So should we conquer it and kick muslims out because it wasn't ok to take that land? What about every muslim country? Muslims stole mecca from the Jews, as is extensively detailed in muslim history books. Should it be conquered and returned?
What about China? The kingdoms did most of the conquering of course, then "unification" took their land and then communists did ethnic cleansing until Han Chinese were in most places all that's left. Hell, a number of the people they cleansed aren't even gone yet. There are still Tibetans. There are plenty of original Hong Kong'ers still alive.
What about Russia? What about North Africa? What about ...
Actually, there were multiple indigenous political entities both along the Eastern Seaboard (where we find those 13 colonies) as well as across what is now the US and Canada[0].
We just took their land and killed most of them, but they were still pretty organized -- with political groupings of various types.
[0] https://scholar.flatworldknowledge.com/books/32177/ourhistor...