The crowd at the funeral service - and thousands online - were visibly emotional by Bush's last conversation with his dad. Afterward, he will be laid to rest at his presidential library in College Station, Texas.
The truce with Trump allows the Bush family, and the nation, to honor the legacy of a president who guided the United States through the 1991 Persian Gulf War and the breakup of the Soviet Union without becoming mired in today's toxic politics.
Obama and Bush's friendship has become a model of bipartisan bonhomie since former President Barack Obama was in office.
"He was a man of such great humility", said Alan Simpson, a former Republican senator from Wyoming. "He stood in the breach in Washington against unthinking partisanship".
The four men first reflected on time spent with America's 41st president, recalling their first show for the late Bush Sr. on the lawn of the White House in October 1983.
Still, there were reminders of lingering tensions.
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President Donald Trump and first lady Melania Trump arrived.
Indeed, the funeral occurred at the same church where services were held in April for Barbara Bush, which was remembered for an emotional scene when the former president gazed from his wheelchair up at her casket, then shook hands with well-wishers.
Rather than a 21-gun salute, the Navy's planned tribute to the late President George H.W. Bush could be called a 21-top-gun salute. The best father a son or daughter could have.
Brit Hume weighed in Wednesday on Rush Limbaugh's contention that the media's praise for George H.W. Bush after his death has been "phony". "I'm much more optimistic because I don't come here often".
In an earlier tweet, Mr Trump said he was "looking forward to being with the Bush family" at the service, scheduled to begin at 11am local time. He will be missed! Trump did not shake hands with Bill and Hillary Clinton, who looked straight ahead. We look at the way USA media facilitated the war on Iraq with journalist John "Rick" MacArthur, president and publisher of Harper's Magazine and the author of the book "Second Front: Censorship and Propaganda in the 1991 Gulf War".
Canadian former Prime Minister Brian Mulroney lauded Bush's role in handling the end of the Cold War and helping the delicate reunification of Germany.
In the crowd sat Jordan's King, Britain's Prince of Wales, Germany's Chancellor and Poland's President, a reflection of a foreign policy hailed as measured and based in core American values. Trump also declared Wednesday a national day of mourning.
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