Americans have reason to trust in progress. By so many different yardsticks, we can gauge improvement just over the past half-century. We are indisputably more tolerant and accepting than we were in the 1960s. The percentage of American women with a college degree is five times greater today than it was in 1964. Back then, millions of black Americans were systematically denied the right to vote in many places, most especially in states of the old Confederacy. By 2012, for the first time in U.S. history, a higher percentage of blacks (66 percent) voted nationally than did whites (64 percent). The poverty rate among the American elderly has been cut by two-thirds, largely attributable to Social Security. (Unforgivably, the poverty rate among the politically powerless, children, remains higher today than it was 48 years ago.) Our air and water are both dramatically cleaner. In just over a half-century, while the U.S. population has not even doubled, the nation’s gross domestic product has increased nearly sixfold. There is much to celebrate.

But moral progress in American public life is much less clear. Take the national campaign of 1964. There was little suspense about the outcome. American voters were in no mood, 11 1/2 months after the national trauma of the assassination of the martyred John F. Kennedy, to switch to a third different president in 14 months — which is what Republican Barry Goldwater would have been. But on Oct. 7, President Lyndon B. Johnson’s closest and most trusted aide, Walter Jenkins, the seemingly happily married father of six children, after a cocktail party at Newsweek’s new Washington office, walked two blocks to a YMCA, where he — along with a 60-year-old Army veteran whom he did not know — was arrested on a charge of indecent sexual behavior in the men’s room.

In this personal tragedy was potentially a campaign game-changer. The top personal assistant to the president — his most trusted staff member, someone who attended national security meetings and who in 1964 could have been vulnerable to blackmail or extortion — was booked by the Washington police for criminal sexual acts. Shortly thereafter, it was revealed that Jenkins had been arrested five years earlier on a charge of loitering for immoral purposes.

For Sen. Goldwater, who knew and liked Jenkins personally and who had served with him in the same Air Force Reserve unit in Washington, this was obviously the opening his campaign needed to make the case that Johnson and the Democrats were the party that condoned, even encouraged, the flouting of society’s traditional values by long-haired, pot-smoking hippie youths. Goldwater’s campaign strategists urged their candidate to use the Jenkins affair to attack Johnson on the issue of moral decay.

But Goldwater, who would tell me in a 1986 private interview that the only two men in his entire political career he ever personally loathed were Richard Nixon and Lyndon Johnson, was not a political hit man. He honorably refused to exploit the personal tragedy of Jenkins to hurt Johnson. He later explained: ”It was a sad time for Jenkins’ wife and children, and I was not about to add to their private sorrow. Winning isn’t everything.”

As so often happens in life, history, in the form of big events, intruded in the 24 hours after the Jenkins story broke. Nikita Khrushchev resigned as the Soviet Union’s leader; Communist China exploded its first nuclear bomb; and a 13-year Conservative government in Great Britain unexpectedly fell to Labour. All these destabilizing developments strengthened the electoral position of the incumbent LBJ and effectively pushed the scandal off the front pages and rendered moot Barry Goldwater’s admirable response. But let us not forget that in a moment of maximum political temptation, Goldwater showed uncommon human decency and character beyond measure. And as you may have noticed, we don’t have an awful lot of either these days.

— Mark Shields is a columnist with Creators Syndicate.