Editor's note: Charles Kaiser is the author of "1968 In America" and "The Gay Metropolis," a former reporter for The New York Times and The Wall Street Journal and a former press critic for Newsweek. He blogs about politics and the press for the Sidney Hillman Foundation.

(CNN) -- "It is possible to read the history of this country as one long struggle to extend the liberties established in our Constitution to everyone in America."

-- Molly Ivins, great American newspaperwoman

Forty years after they ended, the 1960s remain the most controversial decade of the 20th century. Either you believe that they destroyed America, or they cured it.

Put me down as a fervent believer in their success as a cure.

Before 1960, only undivorced white Protestant men had ever served in the White House. Almost 100 years after the Emancipation Proclamation, African-Americans lived in segregated communities and attended segregated schools on both sides of the Mason-Dixon Line, and none attended the all-white state universities of the South.

Gay people were completely invisible, except when they were fired from the federal government (or any company doing business with the federal government, where they were also banned from employment.)

There were no openly gay journalists, doctors, lawyers or professors and only two openly gay public figures in the whole country: James Baldwin and Allen Ginsberg.

Women were denied abortions; in many states they could not buy contraception devices, or obtain national credit cards, or hope to rise to the top of most professions.

The young African-Americans who began the modern civil rights movement in the 1950s provided the model that would change the way everyone in America was treated who was neither white nor straight nor male.

It was the decision of these black men and women to reject the submissive roles white men had reserved for them that legitimized the aspirations of every other victim of oppression.

The movement that came of age in the early 1960s integrated universities, spurred the passage of the Civil Rights Act of 1964 and the Voting Rights Act of 1965, put black faces on TV shows that weren't sports contests and -- most importantly -- provided the blueprint for the liberation of every other oppressed group in the United States.

In no other period of our history did we make such dramatic progress in that never-ending struggle "to extend the liberties established in our Constitution to everyone in America."

The straight sexual revolution sparked by the birth control pill led rapidly to an unprecedented movement toward gay liberation -- partly because the pill had fueled the argument that sexual activity unrelated to procreation was just as useful and important as the other kind is.

The 1950s are often celebrated as the glory days of the postwar period, and in one sense they were, because America still had the most powerful industrial base in the world, propelling millions of Americans into the middle class.

But in every other way they were a period of sterile conformity, when monsters such as Sen. Joe McCarthy of Wisconsin launched witch hunts against mostly imaginary communists, and the federal government fired thousands of employees just because they were gay.

Or, as Hodding Carter put it to historian Arthur Schlesinger, when Schlesinger asked why Southern white men hated Bill Clinton so much, "They look back with longing at the good old days -- the days when abortion was in the back alley, gays were in the closet, women were in the kitchen, blacks were in the back of the bus, and condoms were under the counter."

A significant factor in all of this progress was the fact that organized religion -- and all of the prejudices and superstitions it embodied -- was at one of its lowest ebbs in our history.

That's the social and political side. Then there's the cultural side.

The liberation that was occurring at the polling places and universities was mirrored elsewhere when Aretha Franklin, Marvin Gaye, Diana Ross and scores of other black entertainers were suddenly just as famous and successful as Perry Como and Frank Sinatra.

The music produced in that era by Bob Dylan, Berry Gordy, the Beatles, Jimi Hendrix, the Byrds, the Beach Boys and hundreds of others will endure forever as my generation's proudest artistic achievement.

The Vietnam War was the decade's greatest tragedy -- a completely unnecessary adventure that killed 55,000 Americans and hundreds of thousands of Vietnamese. But those Americans did not die in vain -- because of their sacrifice, the Vietnam syndrome was born.

Wrongly maligned by neoconservatives, this was the syndrome that prevented us from repeating anything like that on a similar scale for more than 30 years -- until George W. Bush and his henchmen embarked upon the equally disastrous and unnecessary invasion of Iraq.

The idealism embodied by John and Robert Kennedy and the Martin Luther King Jr. inspired a whole generation to change the way America was governed, and how millions of Americans would get to live their lives.

Our single greatest failure was to sustain the idea that corporate America is the biggest threat to a vibrant democracy, and today the power of corporate wealth over our politics has never been more absolute.

But unless you truly believe that America was a better place when 99 percent of the positions of power were reserved for straight white men, you cannot deny that the '60s did more to improve our republic than any other era in our history.

The opinions expressed in this commentary are solely those of Charles Kaiser.