It would be very hard to exaggerate the prominence and influence of Charles Schulz’s Peanuts in American culture during the cold war. The artistically revolutionary comic strip both influenced and mirrored the national mood. If the blend of humanity, existential melancholy, and subversive humour captured in Schulz’s minimalist lines seems familiar or even trite to us today it is only because his aesthetic has burrowed so deeply into the psyche of the country.

Collections of Peanuts comics were the first books I can remember demanding that my parents buy for me. Schulz’s influence continues: my complete edition of the comics, inherited from my late uncle, takes up a full bookshelf in our 11-year-old son’s room. He reads them constantly and laughs aloud.

But Schulz insisted that he was a simple craftsman who made something that was mostly meant to be enjoyed and forgotten. One consequence of that was a disavowal of politics. A cartoonist, he said, “is being hired by a newspaper editor and he buys your strip because he wants to sell his newspaper. So why should you double-cross him by putting in things that will aggravate him? That’s not my job.”

He kept his word. A few contemporaries faulted him for this, arguing for the inane view (which has only become more popular since) that it is a lesser artist whose art does not engage with politics. Blake Scott Ball, in Charlie Brown’s America, does not make the mistake of trying to find secret political intentions in Schulz’s comics. What he does show is a deeply decent man who was moved by the moral drama of the world around him. That emotion came through in the comics, which resonated with the political realities confronting his millions of readers.

His approach to the big issues of the day was indeed sometimes cautious. He introduced the strip’s first black character, Franklin, after first rejecting the idea. A white Midwesterner, he thought that drawing a black character would appear patronising. Correspondence with black readers convinced him otherwise, and Franklin made his debut in 1968. It was a big moment in a pivotal year for the country. But Franklin never became as central a character as Charlie, Lucy, Linus or Peppermint Patty.

There are two areas, however, where Ball makes a good case for Schulz leaving a lasting moral, if not political, mark: war and religion. The reasons were personal. Schulz was a combat veteran of the second world war and a Christian.

Snoopy’s alternative identity as a first world war flying ace — with his doghouse propeller plane — was a childhood favourite. It never occurred to me to read the strips as commentaries on the Vietnam war. Yet they were. It is telling that Snoopy never defeated his arch enemy, the Red Baron, and equally notable that the strips became more bleak as the war went on. “I’m exhausted,” Snoopy complains in 1971. “This stupid war is too much.” Readers got the message: Schulz supported the fighting man, not the war. The soldiers in Asia got the message, too.

Schulz’s religious influence was felt most on television. In the 1965 inaugural Peanuts Christmas special the strip’s most religious character, Linus, tells Charlie Brown what the holiday is really all about: the birth of Jesus the saviour. It’s a touching scene, but one that scared the show’s sponsors half to death. It came not long after mandatory school prayer was found unconstitutional by the supreme court, a deeply unpopular ruling. But rather than being preachy or mawkish, it worked perfectly.

Why did this piece of religious art avoid the usual pitfall of such things? Largely because, Ball shows, Schulz rejected the idea of religion as something public or political. He thought school prayer was “total nonsense.” Christianity drew its strength not from the state, or from a TV set, but from individuals finding their own way. That is where great art comes from, too.

Charlie Brown’s America: The Popular Politics of Peanuts, by Blake Scott Ball, Oxford University Press, RRP$34.95, 264 pages

Robert Armstrong is the FT’s US financial editor

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