From the moment he crossed the transept of the soaring Washington National Cathedral, tore off his overcoat and took his seat in the front pew, President Donald Trump was an outsider.
When the others sang an opening hymn, his mouth did not move.
When the others read the Apostles' Creed, he stood stoically.
And when one eulogist after another testified to George H.W. Bush's integrity and character and honesty and bravery and compassion, Trump sat and listened, often with his lips pursed and his arms crossed defiantly over his chest.
Today's state funeral was carefully orchestrated to be about only one man and his milestones - Bush the father, the friend, the war hero and the lifelong public servant.
But inevitably it became about Trump, too, for it was impossible to pay tribute to the 41st president without drawing implicit contrasts with the 45th.
"His life code was: 'Tell the truth. Don't blame people. Be strong. Do your best. Try hard. Forgive. Stay the course,' " Bush biographer Jon Meacham said in his eulogy. "And that was, and is, the most American of creeds."
The mourners did not deliver the searing rebukes of Trump the US witnessed in September for the funeral of Senator John McCain. But despite being crafted to honour Bush's legacy, their words nevertheless also served to underscore the singular nature of Trump's own presidency.
Trump was in the company of all of his living predecessors for the first time today, and the encounter was plainly uncomfortable.
By 10.49am local time, when Trump and wife Melania first stepped into the cathedral, a cool hush had come over the pews filled by American dignitaries and foreign leaders, past and present. Trump handed his black overcoat to a military aide and took his seat on the aisle next to Melania, with three past presidents and first ladies seated to her side.
First was the president Trump said was illegitimate (Barack Obama); then the first lady he called a profligate spender of taxpayer dollars (Michelle Obama); then the president he called the worst abuser of women (Bill Clinton); then the first lady and secretary of state he said should be in jail (Hillary Clinton); and then the president he said was the second-worst behind Obama (Jimmy Carter) and his wife, Rosalynn.
The Trumps and the Obamas greeted each other brusquely, but only Melania Trump reached over to shake hands with Bill Clinton. Hillary Clinton did not acknowledge the Trumps, keeping her gaze straight ahead as if determined not to make eye contact with the man who continues, two years after the 2016 election, to inspire "Lock her up!" chants at his rallies.
The frostiness of Trump's interactions with his predecessors was all the more apparent when former President George W. Bush entered the cathedral a few minutes later. Bush shook hands cheerfully with each of the other presidents and first ladies. He slipped what appeared to be a candy to a smiling Michelle Obama - a sweet reminder of McCain's funeral, when video of Bush giving Obama candies went viral on social media.
As a military honour guard carried Bush's flag-draped casket to rest in front of the altar, the Trumps joined the Obamas and Clintons in holding their right hands over their hearts.
Trump's Cabinet members and aides seemed to blend easily into the audience. Vice-President Mike Pence and his wife, Karen, wandered over to exchange pleasantries with the Clintons and Obamas. White House counsellor Kellyanne Conway and policy director Stephen Miller schmoozed their way through the cathedral's nave. Just behind the presidents and vice presidents, Ivanka Trump sat next to Chelsea Clinton, suppressing from public view any hostility that might exist between them.
It was President Trump who seemed most out of place. For about two hours, he sat in silence, the rare event at which the president was not the centre of attention but merely an observer.
Since learning of Bush's death late last week, Trump has striven to be magnanimous - to act, as he often boasts he could, "presidential".
Trump opened the doors of Blair House for the Bushes to stay. He dispatched Air Force One to carry the late president's body and members of the Bush family to and from Houston. All the while, he has refrained - so far, at least - from publicly reacting to the nearly week-long celebration of Bush's life and its contrasts with Trump's.
The first of Bush's five eulogists was Meacham, a Pulitzer Prize-winning journalist who grew close to Bush as he researched the former president's life for the 2015 biography Destiny and Power. Meacham explained what Bush meant by his famous volunteerism phrase "thousand points of light," which Trump mocked this past summer as an ineffective and confusing slogan.
"Abraham Lincoln's 'better angels of our nature' and George H.W. Bush's 'thousand points of light' are companion verses in American's national hymn, for Lincoln and Bush both called on us to choose the right over the convenient, to hope rather than to fear, and to heed not our worst impulses, but our best instincts," Meacham said.
The next eulogist, former Canadian Prime Minister Brian Mulroney, praised three of Bush's achievements in office - negotiating the North American Free Trade Agreement, the Americans With Disabilities Act and the Clean Air Act.
"There's a word for this. It's called 'leadership,' " Mulroney said. "Leadership. Now, let me tell you that when George Bush was president of the United States of America, every single head of government in the world knew that they were dealing with a gentleman, a genuine leader, one who was distinguished, resolute and brave."
It was not lost on the audience that Trump has slammed Nafta, calling it one of the worst trade deals ever; mocked a journalist's physical disability; and rolled back scores of environmental regulations.
Trump sat through much of Mulroney's speech crossing his arms over his chest, or holding his hands together between his knees, at times leaning forward in his seat.
Trump's body language loosened up when former Senator Alan Simpson delivered a lighter and more humourous remembrance of his longtime friend. Trump laughed as Simpson told stories about serving in Washington with Bush; at one point, Simpson sang the most famous line from the play Evita: "Don't cry for me, Argentina!"
But Simpson, too, conveyed a more serious lesson as he spoke of Bush's humility and kindness. "Those who take the high road of humility in Washington, DC, are not bothered by heavy traffic," he said, adding later, "Hatred corrodes the container it's carried in."
As he assumed the presidency, Bush summoned all Americans to create a "kinder" and "gentler" nation - a message that Trump, then a Manhattan real estate developer and tabloid celebrity, found lacking.
"I like George Bush very much and support him and always will," Trump said in a 1990 interview with Playboy. "But I disagree with him when he talks of a kinder, gentler America. I think if this country gets any kinder or gentler, it's literally going to cease to exist."
At today's funeral, the most emotional eulogy was that of Bush's eldest son, George W., who celebrated his father's character.
"He showed me what it means to be a president who serves with integrity, leads with courage and acts with love in his heart for the citizens of our country," Bush said.
Trump applauded Bush's speech, and then the Rev Russell Jones Levenson jnr, who had been Bush's pastor at St Martin's Episcopal Church in Houston, took to the pulpit to deliver a final, stirring eulogy. His was as direct a reference to the Trump era as any.
"Some have said this is an end of an era," Levenson said. "But it doesn't have to be. Perhaps this is an invitation to fill the void that has been left behind."
After the choir sang and bells rang, after Bush's casket was carried down the centre aisle and as it was loaded into a hearse, the Trumps departed the cathedral quickly through a side exit. The President was whisked back to the White House. He returned to the seclusion and comfort of the Oval Office.