...In nineteenth century Europe there were, essentially, three parties: the conservatives, the liberals, and the radicals. Conservatives sought to defend certain aspects of the old order, most especially the political privileges of the aristocracy, the interests of the landed gentry, and the power and revenue of the established church. Liberals attacked these aspects of the old order by demanding political equality, free trade, and disestablishment. Radicals attacked these aspects of the old order and demanded, in addition, economic equality (and in some cases libertine license).
There were no European-style conservatives in the United States because there was no aristocracy, no landed gentry, and no established church. I am aware that the United States had an “aristocracy” and “landlords,” and that for several decades some states had an “established church,” but none of these were remotely comparable to what existed in Europe. Such conservatives as were present at the founding of the United States were called Tories, and they either emigrated to Canada or England, or learned to hold their tongue.
Setting aside a small (but always growing) radical minority, every American was a political and economic liberal. They may have opposed direct election of senators and supported the tariff, but these were concessions to the realities of a fallen world, and not repudiation of core dogmas. Southern slaveholders defended slavery on the liberal grounds of property rights and constitutional law.
And when everyone is, essentially, a political and economic liberal, there is no need for a word to denote a political and economic liberal. Indeed, when radicalism became a real force with the great immigration wave of the late nineteenth century, Americans used the word American to mean liberal. Beginning around 1880, political and economic liberalism was called Americanism.
...But this is not my concern here. My concern is to argue that, so far as the United States is concerned, there was never a time when the word “liberal” simply meant a proponent of free markets and limited government. This sort of “classical liberalism” was more or less ubiquitous in the United States, so its proponents were simply called American. So far as the United States is concerned, a liberal has always been a culture warrior, and it is simple paltering with history to pretend otherwise. As a culture warrior, the purpose of the American liberal has always been to loosen, or “liberalize,” religious and moral strictures and disciplines.