“Prosperity absorbs all criticism” is a political axiom popularized by Frank Kent (1877-1958), who wrote the newspaper column “The Great Game of Politics” for the Baltimore (MD) Sun. “Prosperity Absorbs All Criticism” was a chapter title in Kent’s influential book, Political Behavior: The heretofore unwritten laws, customs and principles of politics as practiced in the United States (1928). Kent said that Calvin Coolidge wasn’t the best presidential candidate and didn’t have the best ideas in 1924, but he won in a landslide because the nation was enjoying economic prosperity.
 
Kent credited the saying (in a November 1927 column) to C. Bascom Slemp (1870-1943), who served as presidential secretary to Calvin Coolidge (a position similar to the current “chief of staff”). It is not known when Slemp first made the statement—it’s possible that Slemp said “Prosperity absorbs all criticism” at some time during or after the 1924 election.
     
 
Wikipedia: Frank Kent
Frank Richardson Kent (1877–1958) was an American journalist and political theorist of the 1920s and 1930s. Although a Democrat, by the 1930s he was one of the leading conservative critics of the New Deal of Franklin D. Roosevelt, with a daily column that reached millions of newspaper readers across the country.Historians group him with David Lawrence, Walter Lippmann, Mark Sullivan, and Arthur Krock as influential political commentators in the 1930s.
 
He was based in Baltimore, where he started as a cub reporter for the Baltimore Sun in 1900. After 1922 the Sun papers syndicated his daily column of political commentary to 140 papers nationwide. Franklin D. Roosevelt in 1922 so admired Kent that he helped him to get his column syndicated. He was one of the big-name journalists who covered the Scopes “Monkey Trial” in 1925. But by 1934 Kent, a lifelong Democrat, turned against the New Deal. He criticized FDR and liberals who tried to disrupt his cherished Jeffersonian principles - the balanced budget, limited spending by the federal government, and a limited government. As his criticism became more severe, he charged that the Democrats no longer stood for states’ rights.
 
Wikipedia: Bascom Slemp
Campbell Bascom Slemp (September 4, 1870 – August 7, 1943) was an American Republican politician. He was a six-time United States congressman from Virginia’s 9th congressional district from 1907 to 1922 and served as the presidential secretary to President Calvin Coolidge. As a philanthropist, Slemp set up the “Slemp Foundation”, which provides gifts and scholarships to schools and colleges in Southwestern Virginia.
         
15 November 1927, Baltimore (MD) Sun, “The Great Game of Politics” by Frank R. Kent, pg. 1:
THOUGH it is true, as the sly Mr. Slemp with a satisfied smile so astutely says in accounting for Republican strength and the futility of Democratic attack that “prosperity absorbs all criticism,” it does seem that to the reflecting few there would come occasionally, as they consider certain facts, a feeling that this would be a pretty sad sort of country if it were not for the Democrats, regardless ot their dissensions, stupidity and short comings.
 
Google Books
Political Behavior:
The heretofore unwritten laws, customs and principles of politics as practiced in the United States
By Frank R. Kent
New York, NY: W. Morrow
1928
Pg. 108:
CHAPTER XI
Prosperity Absorbs All Criticism
 
8 November 1928, Baltimore (MD) Sun, “The Great Game of Politics” by Frank R. Kent, pg. 1:
It was that practical person, C. Bascom Slemp, who some years ago expressed the basic political axiom that “Prosperity Absorbs All Criticism.”
 
Google Books
American Parties and Politics;
History and role of political parties in the United States
By Harold R. Bruce
New York, NY: H. Holt and Co.
1932, ©1927
Pg. 184:
It is the testimony of every political worker everywhere that prosperity absorbs all criticism and the lack of it negatives all achievements.
 
Google Books
Politics, Parties and Pressure Groups
By V. O. Key
New York, NY: T. Y. Crowell Company
1943, ©1942
Pg. 626:
That finding recalls Frank Kent’s maxim, “Prosperity absorbs all criticism.”
 
Google Books
4 July 1960, Life magazine, Editorial, pg. 32, col. 2:
The axiom that “prosperity absorbs all criticism” had been intuitively understood by political pros from Jackson on, but got engraved in granite in the Coolidge landslide of 1924. Then, as the late Frank R. Kent pointed out, the Democrats had the finer candidate (John W. Davis) and better issues, while the Republicans carried a pervasive taint of corruption that led even to the White House itself. But the Republican party “benefiting by a prosperity greater than had existed in any other country at any other time…needed neither issue nor candidate. It was completely impregnable.”