Trump Is Invited to Bush's Funeral Because 41st Commander-in-Chief Didn't Want to 'Stiff' Him

President Donald Trump and First Lady Melania Trumpplan to attendGeorge H.W. Bush‘s funeral — and according to a presidential historian who knew Bush, the former president included Trump in order to not “stiff a sitting president.”

Douglas Brinkley, a Rice University history professor and author, tells PEOPLE that Bush’s decision was motivated by his reverence for the office that he once held.

“For Bush 41, Trump is the president, and he does not want to stiff a sitting president, so in his own way, it is magnanimous that he is having Melania and Donald Trump come,” Brinkley says of Bush, who died at age 94 on Friday.

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Brinkley believes that Bush’s wishes may affect Trump, 72, personally. “In its own way, it may normalize the estrangement Trump feels from the so-called establishment that Bush personified,” he adds.

Brinkley suggested that Bush had mixed feelings about the Trump era. “I think that [Bush] had such respect for the institution of the presidency that Trump annoyed him because he was trying to divide the country at times,” Brinkley tells PEOPLE.

“Nevertheless, when it came to being a stalwart Republican, he was for Judge [Brett] Kavanaugh‘s confirmation. He wanted to see Republican friends of his get posts in government,” Brinkley comments.

Kavanaugh’s confirmation to the Supreme Court in October was controversial after he was accused by multiple women of sexual assault. He denied the allegations.

Bush’s son, former President George W. Bush, showed support for Kavanaugh — who worked for his administration — in the wake of the scandal, telling Politico in September that he and wife Laura Bush “have known and respected Brett Kavanaugh for decades, and we stand by our comments the night Judge Kavanaugh was nominated.”

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“He is a fine husband, father, and friend — and a man of the highest integrity. He will make a superb Justice of the Supreme Court of the United States,” George W. Bush previously said.

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Brinkley mentioned Barbara Bush‘s funeral, which Mrs. Trump attended but Trump did not. The former first lady died at age 92 in April.

“But the cruder aspects of Donald Trump — the mean Twitters and the name calling — [Bush] found that gauche, and that is why Barbara Bush did not want Donald Trump at her funeral,” he says.

The White House said in a statement in April that Trump was skipping Mrs. Bush’s funeral “to avoid disruptions due to added security, and out of respect for the Bush family and friends attending the service,” the Associated Press reported at the time.

Bush’s state funeral will be held at the National Cathedral in Washington, D.C., on Wednesday at 11 a.m. ET. In a presidential proclamation, Trump declared that Wednesday would be dedicated to Bush’s memory and that flags should be lowered to half-staff in his honor for 30 days.

“President George H.W. Bush led a long, successful and beautiful life,” Trump tweeted. “Whenever I was with him I saw his absolute joy for life and true pride in his family. His accomplishments were great from beginning to end. He was a truly wonderful man and will be missed by all!”

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In a statement, the Trumps wrote about Bush’s legacy, including Bush’s signature phrase about volunteerism, “a thousand points of light,” that Trump had ridiculed at a rally in July.

“Through his essential authenticity, disarming wit, and unwavering commitment to faith, family, and country, President Bush inspired generations of his fellow Americans to public service — to be, in his words, ‘a thousand points of light’ illuminating the greatness, hope, and opportunity of America to the world,” the statement read.