That's really not true. US political and economic thought heavily centered around individual proprietors and farmers before the civil war, and was deeply suspicious of large corporations. In some states you could only form a joint stock company for time & scope limited things, such as building a canal.
It's only after the Civil War and into the Gilded Age do we see the rise and acceptance of large scale corporations, but not without conflict. Modern readers will be surprised to know that Marx was relatively popular among Americans in the west during his lifetime (among those that read, naturally), certainly in part due to the increasingly corporate focus that the American economic system was taking at the time.
It's only after the Civil War and into the Gilded Age do we see the rise and acceptance of large scale corporations, but not without conflict. Modern readers will be surprised to know that Marx was relatively popular among Americans in the west during his lifetime (among those that read, naturally), certainly in part due to the increasingly corporate focus that the American economic system was taking at the time.