Truman's failures before politics shaped his later resolve

Long before Washington, Truman spent over a decade as a struggling Missouri farmer and later ran a haberdashery that went under, leaving him in debt for years afterward. McCullough treats this stretch not as a wasted detour but as the forge of Truman's character: a man who had genuinely failed, repaid his debts slowly and without complaint, and knew what it felt like to be ordinary and unrecognized.

This matters because it inoculated him against the vanity that often accompanies power. When he unexpectedly became president, he didn't carry an inflated sense of his own destiny; he carried the residue of a man who had scraped by, which McCullough argues made him more attentive to consequences for regular people than a more privileged path might have.

The farm years also gave him a physical stamina and an unpretentious manner that stayed with him permanently, distinguishing him sharply from the patrician Roosevelt he succeeded.

Takeaway: real preparation for high responsibility sometimes looks like ordinary failure, endured with integrity.