[17] Historian Allison Dorsey wrote in The American Historical Review that the book is "well-researched, persuasively argued" and "a brilliant analysis of race, class, and politics".

[18] Historian Amanda I. Seligman wrote in the journal Urban History (CUP) that the book provides an "important contribution to the scholarship on the political significance of cities and suburbs in the late twentieth-century United States" pointing its greatest strength in "its reading of the subtleties of local and national politics" but criticized "Kruse's identification of Atlanta as the originator of modern conservatism" as exaggerated.

[21] Historian Axel R. Schäfer reviewing the book in The American Historical Review, wrote that the book is "intriguing and insightful" but stated that "it revels too much in human-interest stories and ad hominem arguments" and that it's "too focused on the idea that Christianizing the nation was a marketing ploy designed by corporate titans who enlisted conservative clergymen in an effort to construct a Christian libertarianism capable of defeating the New Deal".

Americans easily accepted placing God's name on their currency and in the oath children recite every school day because similar invocations were already routine in public discourse — from the Declaration's reference to the “unalienable Rights” endowed by the “Creator” to the official chaplains who have opened sessions of the House and Senate with a prayer since 1789.

[25] Barton Swaim, writing for The Wall Street Journal, was more critical, saying: "In “Fault Lines,” conservatives are almost invariably the aggressors in the culture wars and so primarily responsible for the widening gulf between Americans of left and right."

The article discussed how Jim Crow segregation, the building of the highway system in the United States, and opinions on public transit have affected African American communities, particularly in Atlanta and other Southern cities.

[32] In June 2022, Phillip W. Magness (of the American Institute for Economic Research) in Reason accused Kruse of plagiarism in his 2000 doctoral dissertation, his 2005 book White Flight, and other works.

"[34] The Daily Princetonian and The Chronicle of Higher Education, which discussed the story, both noted past animosity between Magness and Kruse on politically fraught academic matters.

"[34][35] In October 2022, Kruse stated on his Twitter account that both Cornell, where he wrote his dissertation, and Princeton, where he is employed, ultimately determined that these were "citation errors" and did not rise to the level of intentional plagiarism.

"[37] In The Atlantic, academic Tyler Austin Harper expressed skepticism of Princeton's conclusion, writing "“careless cutting and pasting” seems to be a pretty good working definition of plagiarism.