Biden’s Cancer Diagnosis Leaves Democrats With New Questions

Former President Joseph R. Biden Jr.’s announcement that he has aggressive prostate cancer has derailed Democrats’ nascent effort to acknowledge where they went wrong on his presidency and 2024 candidacy, as the party wrestles with a complicated mix of sympathy and unsettling new questions about his health.

In recent days, prominent Democrats had begun to self-examine their role championing Mr. Biden’s re-election bid despite his signs of aging and voters’ clear preference for a younger candidate. Some accused him and his top aides of concealing his mental and physical decline, setting up a last-minute candidate switch that culminated in Democrats’ defeat.

Now, top Democrats’ conversation about Mr. Biden has shifted to well wishes and statements of concern for the former president, whose office said on Sunday that he had a serious form of cancer that has spread to his bones. The grim development has made recriminations about his role in his party’s calamitous 2024 loss appear disrespectful, pausing efforts by younger leaders to treat the subject with new honesty.

On Monday morning, Mr. Biden expressed gratitude for the outpouring of sympathy, sharing a photo on social media of him smiling next to his wife, Jill, and their cat, Willow. He thanked supporters for “lifting us up with love and support.”

Yet the reaction to Mr. Biden’s disclosure also demonstrated how his legacy has been altered by his decision to run for re-election as the oldest president in history.

Mixed in with the prayers were a few whispered uncertainties that reflected a lingering lack of trust in what he and those closest to him say about his health. Text chains among Democrats who worked on the 2024 campaign lit up with questions: When did he learn he had prostate cancer? What if he had stayed in last year’s race and won?