He then returned to the University of Iowa to teach English composition before rejoining United Press, this time in New York.

In 1925, Childs rejoined United Press and then in 1926 joined the St. Louis Post-Dispatch, where he would remain off and on until 1944,[2] mostly serving as a feature writer for its American Mercury magazine section.

"River Town," a collection of thinly disguised tales of prominent Clinton citizens, was thought by natives to be at best in poor taste, and at worst, outrageous, although it was read by many with glee.

(In 1951 Childs partially redeemed himself in the eyes of the offended with an article, "The Town I Like—Clinton, Iowa," which appeared in the May–June issue of the Lincoln-Mercury Times).

He traveled 15,000 miles with President Franklin D. Roosevelt during the 1936 re-election campaign, and briefly with candidates Alfred M. Landon and Norman Thomas.

Critics agreed that it showed "striking observation, faithful reporting, and vigorous journalism of a high order"; President Roosevelt was inspired to send a special commission abroad to study European cooperative systems.

Childs sued Guffey for slander, won a full apology on the floor of the Senate, then withdrew the suit.

In the early 1940s, Childs published several books that won renewed critical acclaim: Toward a Dynamic America with William T. Stone; This Is Your War ("succinct and stimulating," said The New York Times); and I Write from Washington.

During the spring of 1943, as guest of the Swedish Foreign Office, Childs again visited Sweden and became interested in the role of neutrals in World War II; this led him to investigate conditions in Switzerland, upon which he reported in a Saturday Evening Post article.

Relaxation for Childs during the war years came with horseback riding and figure skating—"When you're trying to keep your balance on a backward eight, you can't think about either your own or the world's troubles."

He began writing his column Washington Calling in February 1944 and published The Cabin (an autobiographical novel) that year: " 'Some day,' he said, 'I'll ride on trains whenever I want to ...

"During another stint with the Post-Dispatch (1954–1962), Childs wrote essays for American Heritage and Holiday and published: Ethics in a Business Society, which was translated into Japanese and Portuguese; The Peacemakers, which appeared in foreign language editions in Denmark, Sweden, The Netherlands, and France; The Ragged Edge: The Erosion of Individual Liberties; and best-sellers Eisenhower: Captive Hero and Walter Lippmann and His Times, co-edited with James Reston.

[2] On November 21, 1947, Childs wrote an essay that exposed the Justice Department's grand jury investigations into Soviet espionage and all but named Elizabeth Bentley as a witness.

The grand jury investigations led to congressional testimony before the House Un-American Activities Committee by not only Bentley but also Whittaker Chambers during the summer of 1948 (during the presidential campaign season).

In 1945, Childs received the Sigma Delta Chi Award for "sustained insight in national affairs, first hand reporting, and effective writing."