As President Barack Obama prepares to leave office, we should take a moment to appreciate his heroic demonstration of thick skin for the past eight years.

While he departs with high public approval, Obama is reviled by a virulent minority that observes few boundaries of decency in attacking him.

Our first black president was subjected to malicious lies that he was born in Kenya and not Hawaii.

His Christian faith was disrespected by far-righters who painted him as a Muslim bent on imposing Sharia, or Islamic law, on America.

He endured a back-bench GOP congressman shouting “liar” as he delivered his State of the Union speech.

He heard his beautiful wife referred to by a Republican functionary as “a gorilla in high heels.”

In historically unprecedented obstructionism, GOP leaders refused to work with him on just about anything, closing the government to avoid negotiating with him and refusing even a hearing for his Supreme Court nominee, making no secret that Obama’s failure mattered more to them than America’s success.

Now the incoming Trump administration and Republican Congress are determined to erase every mark of his presidency, as though he were some kind of stain.

Perhaps the greatest insult was having to listen to eight years of denials that any of this was racially motivated.

But through it all, the thick-skinned Obama kept his cool, never rising to the bait and responding in kind; often, his most effective weapon in fighting back was a cutting sense of humor.

He was ever the optimist, doggedly calling his fellow Americans to their highest nature rather than their lowest prejudices and jealousies.

And despite the obstruction, he found ways to help to pull the country out of the Great Recession, pass comprehensive health-care reform that had eluded others, protect the environment, expand national parks and monuments, normalize relations with Cuba and engineer a historic international climate-change accord.

However his successors try to blot his legacy, his presidency will be remembered as one of the most consequential of the last half-century.

Obama came into office on a message of optimism, hope, decency and civility, and he’s going out the same way.

In his farewell address, he didn’t buy into the end-of-the-world view of Donald Trump’s election, instead telling countrymen that in spite of the challenges, he still has faith in the American people and our democratic institutions.

He encouraged his fellow Americans to join him in becoming citizen activists for factuality, compassion, understanding and inclusiveness.

Those who haven’t appreciated his high tone and scandal-free administration will see the difference when the most thin-skinned man in America takes over the job.

Maybe someday Obama will get credit for having it right all along on what it takes to make America great again.

Reach David Shapiro at volcanicash@gmail.com.