Ross K. Baker

Opinion columnist

Hesitant, surprisingly inattentive and, at times, almost befuddled, Special Counsel Robert Mueller struggled bravely through Wednesday's hearings before two congressional committees.

For even the most robust 74-year-old it would have been an ordeal. Perhaps we expected him to project the fortitude that earned him that Bronze Star in Vietnam a half century ago and the vigor he displayed as the FBI director after 9/11, two decades in the past. Aging takes its toll on both mind and body and Mueller’s halting performance should serve as a cautionary tale about the age of people who occupy the highest positions in our government.

Older politicians serve everywhere in the government

There are exceptional octogenarians like Justice Ruth Bader Ginsberg or the late Justice John Paul Stevens who could well have served productively into his nineties, but they are exceptions. A more typical problem of high-impact public service on the aging mind and body is 81 year-old Commerce Secretary Wilbur Ross who has been ineffective at his job and seems to spend much of his time currying favor with President Donald Trump. We obviously do not all age at the same pace, but it is more likely that our faculties will grow less acute as we age than it is for them to sharpen.

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Right now there are three men in their mid-to-late seventies under consideration for the 2020 presidential contest. The list is topped by the incumbent, 73-year-old President Trump and two Democratic rivals a few years older, Senator Bernie Sanders and former vice president Joe Biden.

Sanders, because he has been cranky and disputatious for his entire political career, shows the ravages of age less visibly than the more genial former vice-president. Biden’s slack performance in the June Democratic debate has been a source of concern to his staff and his many backers. It has certainly cost him support in public opinion polls. Trump, due to his stream-of-consciousness style and his ability to retain the support of his base despite his contempt for facts is somewhat less vulnerable to charges that he is over the hill. He can tweet effectively from the comfort of a sofa in the White House and his lapses in spelling, grammar and logic are so common that they usually go unremarked.

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There is precedent for electing old or sick presidents

Presidents impaired by age or infirmity are not uncommon. Assassination, which is not age-related, has taken the lives of four presidents but others have succumbed to serious ailments at an age younger than any of today’s presidential hopefuls.

From William Henry Harrison who, in an effort to prove his vitality at the age of 68, gave his lengthy March 1841 inaugural address in a icy rainstorm and died a month after being sworn in, to Woodrow Wilson who suffered a stroke at age 63, to Ronald Reagan whose latter years in the White House were blighted by onset of dementia, the shadow of presidential fragility has always hovered over the White House.

We tend to project positive qualities on to those who we admire and politicians are acutely conscious of the need to display vitality and vigor. President Kennedy suffered from a variety of ailments from chronic back problems to Addison’s disease but photos and footage of him never give any hint of the underlying pain and discomfort he experienced. A clean bill of health for presidential hopefuls is a document intrinsically more important than their tax returns.

Publicly betraying infirmity or incapacity is toxic for presidential vanity. Franklin Roosevelt’s challenge was not age but paralysis from polio and he went to considerable lengths to avoid exposing to public view the braces on his legs or his use of a wheelchair.

Talking about age is important when it comes to the president

Raising the question of a candidate’s advanced age may be insensitive but it is not irrelevant. Impairment of short or long-term memory can prove embarrassing for people in public life. When Robert Mueller failed to remember who appointed him to his first post as an U.S. attorney it signaled a vulnerability that detracted from the cogency of his presentation.

In my own job as a professor, I find myself leaning more heavily on my lecture notes and revise them every year to root out dated references. I no longer mention Bill Clinton without explaining that he was president from 1993 to 2001. Refer to something Ronald Reagan said and I might as well be quoting Oliver Cromwell. If an older professor makes quaint references it may be puzzling or even charming, but someone whose hands are on the awesome instruments of war requires sound judgement and an agile mind.

Ross K. Baker is a distinguished professor of political science at Rutgers University and a member of USA TODAY's Board of Contributors. Follow him on Twitter: @Rosbake1