In any case, he's endured more wear and tear than the normal AARP member. As a Navy pilot during the Vietnam War, he broke both arms and a leg in a crash after his plane was shot down. He spent five and a half years being tortured, beaten and half-starved as a prisoner of war in North Vietnam. He's had surgery twice for melanoma, the deadliest form of skin cancer. All of those misfortunes exact a toll that may offset his hardy genes.
In other lines of work, everyone accepts that there is such a thing as too old. Some major corporations force chief executives and directors to step down at age 65 or so. Airline pilots have a mandatory limit of 60, which the Federal Aviation Administration has decided to raise to 65. Law firms often put partners out to pasture once they reach the golden years.
In those jobs, a fixed age limit makes less sense than it does for the one McCain wants. If a lawyer can no longer handle the work, after all, the firm can promptly cashier him or her. But the voters may never know if a president is growing befuddled by routine tasks -- or if a president, wearied by age, has simply lost the energy needed to perform well. And even if such facts became known, the public may not be able to force his removal.
That's not a big deal for a senator, who can't do much without 50 other people. But for the person occupying the most consequential office on Earth, it's an alarming prospect. John McCain has done a lot of things for his country. He could do one more service by acknowledging that the presidency is a job for a younger person.