Would President John McCain forget who made that 3 am call to the special White House phone? I suspect that his aides would not just let him nod off back to sleep, even if they were intimidated by the prospect of one of his alleged intemperate outbursts, but might our septuagenarian President be less than fully focused?

Most likely he would be, although as someone born in the same year as the senator, I too bristle at suggestions that age has made me less perfect than I once was. But it has. Sadly, those brain cells do go, and "senior moments" of befuddlement are more than a joke. But that shouldn't automatically disqualify one of us still-agile silver foxes from the White House, as few of my contemporaries are likely to turn in a worse performance than the much younger current occupant. However, looking at the top two men in the present Administration, the age question does make a compelling case for very carefully evaluating McCain's vice-presidential choice.

That was my point when I raised the age issue on a Los Angeles Times Book Festival panel last Sunday, and my sparring partner, right-wing radio pundit Hugh Hewitt, wanted me instantly voted off the island of constant noise. He compared my "ageist" comment to someone making a racist charge against Barack Obama.

I take his point, as absurd as it first appeared. Absurd because it is obviously true that aging, as opposed to skin color or gender, does have a deleterious effect on one's physical and mental functioning, and to deny this evident biological reality is as nonsensical as denying evolution itself. The species survives when each generation burns out and is replaced by a hopefully superior one, and while it is natural to want to linger on the scene as long as possible, we cannot insist on our personal indispensability to the continuation of the human experience.

Of course Hewitt was not doing anything of the sort, any more than he would genuinely embrace creationism, summarily dismiss fears of global warming or otherwise honestly endorse the tenet of the sort of phony science that right-wing pundits must from time to time condone. They do so for opportunistic reasons, and that is why the significance of McCain's age must be denied by those eager to maintain the GOP's hold on the presidency. They will hold their noses and vote for him despite the sensible positions he has at times had the temerity to advance, impervious to their blackmail. Impervious, that is, until he decided to make a second run for the presidency, leading him to sharply reverse his past principled stances and accommodate torture, tax cuts for the rich, Pat Robertson and other favored fetishes of the Republican base. The right-wing talk show bully boys still don't trust him, but he's the only horse left to ride.

While they continue to loathe him for his fatal flaw of occasionally embracing a moderate thought, they are dependent upon his electoral victory to extend their vastly disproportionate political power. They fully expect McCain to betray key points of their cryogenic agenda; on Sunday, Hewitt condemned most of McCain's Senate performance and in particular his reasonable stance on immigration.

Their hope of retaining influence rests on saddling McCain with a proven rightist as his vice-presidential choice. The hunt is now on for the new Cheney, but such a candidate has to be brought in under the radar because the public is for the first time in modern history keenly aware that the Vice President can play an enormously destructive role. That is particularly true if the potential President himself is, actuarially speaking, more likely to kick the bucket. Or, less dramatically, simply underperforms.

Let's not kid any longer. Age is a factor in this race and nowhere is it so important as in McCain's vice-presidential choice. If he picks from the very thin ranks of reasonable Republicans, it will be reassuring to more moderate voters attracted to McCain for his independence of thought as reflected in support of campaign finance reform and his opposition to some outrageously bloated military weapons expenditures that he has on occasion done much to expose. But if he turns to the loony wing for a running mate, we must become very concerned about the ability of a man in his 70s to fully perform in the world's most important office. Is there another Cheney lurking in the wings?

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