Are Biden and Sanders too old to be president?

In the Washington Examiner, Byron York writes,

But there is a much simpler point to be made about Biden and Sanders. They are too old to occupy the nation's highest office, not because they are out of touch or because their records are out of line with today's sensibilities, but because they are just too old.

For those who respond, "Well, what about Trump?" remember: If the president serves two terms, he will leave the White House at 78, the oldest ever in office. But that is the age Biden would begin his presidency. And Sanders is a year older.

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