What did Herbert Croly mean when he said, "That homogeneity [of our nation] has disappeared never to return"?

In this
passage, Croly refers to a "homogeneity of feeling" between Americans that was based
in social and economic realities. He argues that throughout most of the nation's history,
Americans, because socioeconomic divides were not very pronounced, generally viewed their place
within the nation in similar ways. They also agreed with each other, for the most part, on
cultural matters such as religion. Croly is concerned that the economic and social changes
associated with the late nineteenth century have shattered this homogeneity of feeling in a
number of different ways that would be recognizable to modern readers. There is a divide between
urban centers and rural areas, between different ethnicities, and especially within the working
classes and wealthy capitalists. This breach, he says, is permanent. The old sense of
homogeneity (which even some intellectuals of his own time rejected in any case) is not coming
back. Croly states the need for a new solidarity in order to maintain democracy, a
"comprehensive coherent democratic social ideal." He saw this new solidarity
proceeding from a strong national government, one which would regulate and control big
corporations, and which would take on a very activist role in dealing with the economy. He was
not advocating for socialism and indeed supported the concept of wage labor but believed that in
the absence of a strong, democratic centralized federal government, the country would split
apart under the social pressures created by the changes of the post-Civil War
era.

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