Barack Obama and his wife, Michelle, wave, accompanied by their daughters, Sasha, 7, and Malia, 10, during an election-night rally in Chicago on Nov. 4, 2008. (Jae C. Hong/Associated Press)

Hold on to one image from President Obama’s farewell address: the president using his handkerchief to wipe a tear from his eye as he thanked Michelle Obama for her grace and forbearance.

The first lady was holding back tears, too, as was her daughter Malia. Politics aside, it was a touching moment in the life of a family we have come to know so well — one of countless such moments, and images, that have changed this nation forever.

The White House is really a glass house, and for eight years we have watched the Obamas live their lives in full public view. We’ve seen a president age, his hair graying and his once-unlined face developing a wrinkle here, a furrow there. We’ve seen a first lady change hairstyles and model an array of designer gowns. We’ve seen two little girls grow into young women.

We’ve seen it all before — except that we’ve never seen an African American family in these roles. Images of the Obamas performing the duties of the first family are indelible, and I believe they will be one of the administration’s most important and lasting legacies.

Visuals are uniquely powerful. They rearrange and reorient our thinking in ways that are difficult to describe or even comprehend. They penetrate to our deepest levels of consciousness without being attenuated by the filter of language; they retain their specificity, their emotional sharp edges. They can make us laugh, cry, rage and weep without us quite knowing why.

(Victoria Walker/The Washington Post)

For eight years we have had the privilege of seeing a black family live in the White House. I still find that hard to believe.

We watched as the president, the first lady, Malia and Sasha walked across the South Lawn to board Marine One. We watched the president playing with the family dog, Bo. We watched Michelle Obama working in her garden. Those who live in Washington might have glimpsed the girls stopping by McDonald’s on their way home from school, or the president and first lady having a date night at one of their favorite restaurants.

We saw the Obamas host glittering state dinners. We saw them walk down the stairs of Air Force One onto red-carpeted tarmacs around the world. We saw President Obama channel the pride of the nation at moments of triumph, as when he announced the raid that killed Osama bin Laden. And we saw him become a conduit for our despair after the Newtown school massacre, the Charleston church killings and so many other senseless acts of gun violence.

Given this country’s history of slavery and discrimination, the first black family to serve as first family had to be like a fortress, strong and unassailable. In that sense the Obamas were from central casting — so impeccable in education, elocution and etiquette that even the president’s harshest political critics spoke of them as a family with genuine admiration.

We watched as Obama largely abandoned recreational basketball, the scourge of tendons and ligaments, for a more age-appropriate pastime. The golf course became, for him, the “third space” (besides home and family) that some men seem to need. According to a website that tries to keep track, Obama has played more than 300 rounds of golf during his tenure. Unlike other presidents, he almost never used these outings to butter up political adversaries or reward loyal allies. Instead, he stuck mostly to a tight group of regulars, with a few luminaries, mostly professional athletes, tossed in.

When he wasn’t working — and, reportedly, sometimes when he was — the president watched ESPN.

As a rule, Obama went upstairs to the residence every evening so the family could have dinner together. Then he would go back to work for a while before bedtime.

As Obama noted Tuesday night, one of his wife’s great accomplishments was opening the doors of the White House as wide as possible to the American people. Every December, she and the president put themselves through a long march of holiday parties, including two for the media. At the end of the evening, having shaken hundreds of hands and posed for hundreds of smiling pictures, any normal human beings would have been homicidal, suicidal or both. But the Obamas were unfailingly sunny and gracious, making every single guest feel welcome in their home.

In their time in the White House, the Obama family expanded this nation’s idea of what it can achieve. They gave us vivid images that will never fade. We owe them heartfelt thanks for being, at all times, the classiest of class acts.

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