Well, you are mistaken. The classical definition of liberal economics always included minimal regulation of free markets. This was understood as a more progressive, efficient, and scientific approach. The traditional conservative view was that established economic interests should be protected, to promote social stability. Most people calling themselves economic conservatives today would have found themselves solidly in the liberal camp 100 years ago. If heavily regulated markets seem unamerican, it’s mostly because America has always been a liberal project, with rare exceptions.
I agree. My observation was that the term "capitalist" is a Marxist concept. Classic liberals did not consider themselves "capitalists". Yes, today we would call classic liberals conservatives. Socialists stole the words "progressive" prior to WWI and "liberal" in the thirties as aphoristic fig leaves for their base intentions. When the Catholic church refers to "unbridled capitalism", "unfettered capitalism" and "progressivism", they demonstrate their need for a history lesson.
From Wikipedia:
The term capitalism, in its modern sense, is often attributed to Karl Marx. In his magnum opus Capital, Marx wrote of the "capitalist mode of production" and revealed its laws of functioning using a method of understanding today known as Marxism. However, Marx rarely used the term "capitalism", although it was used twice in the more political interpretations of his work, which were primarily authored by his collaborator Friedrich Engels.