Former President Barack Obama speaks at a memorial service for Sen. John McCain, R-Ariz., at Washington National Cathedral in Washington, Saturday, Sept. 1, 2018. McCain died Aug. 25, from brain cancer at age 81. (AP Photo/Pablo Martinez Monsivais)
Pablo Martinez Monsivais/AP
Former President Barack Obama speaks at a memorial service for Sen. John McCain, R-Ariz., at Washington National Cathedral in Washington, Saturday, Sept. 1, 2018. McCain died Aug. 25, from brain cancer at age 81. (AP Photo/Pablo Martinez Monsivais)
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WASHINGTON, DC - SEPTEMBER 1: Cindy McCain looks on as a joint military service casket team carries the casket of the late Senator John McCain following his funeral service at the Washington National Cathedral, September 1, 2018 in Washington, DC. Former presidents Barack Obama and George W. Bush delivered eulogies for McCain in front of the 2,500 invited guests. McCain will be buried on Sunday at the U.S. Naval Academy Cemetery. (Photo by Drew Angerer/Getty Images)
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WASHINGTON, DC - SEPTEMBER 1: Cindy McCain looks on as a joint military service casket team carries the casket of the late Senator John McCain following his funeral service at the Washington National Cathedral, September 1, 2018 in Washington, DC. Former presidents Barack Obama and George W. Bush delivered eulogies for McCain in front of the 2,500 invited guests. McCain will be buried on Sunday at the U.S. Naval Academy Cemetery. (Photo by Drew Angerer/Getty Images)
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Secretary of Defense James N. Mattis and Chairman of the Joint Chiefs of Staff Marine Gen. Joseph F. Dunford Jr. will brief the media on Tuesday, Aug. 28, at 10 a.m. EDT, in the Pentagon Briefing Room (2E973).  DAILY SCHEDULE: Secretary of Defense James N. Mattis and Chairman of the Joint Chiefs of Staff Marine Gen. Joseph F. Dunford Jr. brief the media at 10 a.m. EDT in the Pentagon Briefing Room (2E973). Both U.S. and foreign journalists without a Pentagon building pass must be pre-registered in the new Pentagon Visitor Management System to attend this briefing; plan on being escorted from the River Entrance Pedestrian Bridge or the Pentagon Metro Entrance Facility only. Please arrive no later than 45 minutes before the briefing; have proof of affiliation and photo identification. Please call 703-697-5131 for any questions and escort into the building. The briefing will also be streamed live on www.defense.gov/live.  Secretary of Defense James N. Mattis hosts an enhanced honor cordon welcoming Minister of Defense Ryamizard Ryacudu of Indonesia, to the Pentagon at 2:30 p.m. EDT on the steps of the River Entrance. All journalists desiring to cover the cordon must obtain a wristband from security screening. Journalists without a Pentagon facility access card must go through security screening at the base of the River Entrance Pedestrian Bridge, and will be escorted to the cordon from there. Security screening will begin at approximately 1:45 p.m. EDT; have proof of affiliation and two forms of photo identification. Journalists with a Pentagon facility access card, and whom have entered the building prior to 1:30 p.m. EDT, may go through security screening at the River Entrance to obtain their wristband. All journalists wishing to cover the honor cordon, including those with a Pentagon facility access card, must be in place no later than 2:15 p.m. EDT. Once security screening has been initiated at the base of the bridge, all journalists entering the building via the bridge for any reason, including those with a Pen
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Secretary of Defense James N. Mattis and Chairman of the Joint Chiefs of Staff Marine Gen. Joseph F. Dunford Jr. will brief the media on Tuesday, Aug. 28, at 10 a.m. EDT, in the Pentagon Briefing Room (2E973). DAILY SCHEDULE: Secretary of Defense James N. Mattis and Chairman of the Joint Chiefs of Staff Marine Gen. Joseph F. Dunford Jr. brief the media at 10 a.m. EDT in the Pentagon Briefing Room (2E973). Both U.S. and foreign journalists without a Pentagon building pass must be pre-registered in the new Pentagon Visitor Management System to attend this briefing; plan on being escorted from the River Entrance Pedestrian Bridge or the Pentagon Metro Entrance Facility only. Please arrive no later than 45 minutes before the briefing; have proof of affiliation and photo identification. Please call 703-697-5131 for any questions and escort into the building. The briefing will also be streamed live on www.defense.gov/live. Secretary of Defense James N. Mattis hosts an enhanced honor cordon welcoming Minister of Defense Ryamizard Ryacudu of Indonesia, to the Pentagon at 2:30 p.m. EDT on the steps of the River Entrance. All journalists desiring to cover the cordon must obtain a wristband from security screening. Journalists without a Pentagon facility access card must go through security screening at the base of the River Entrance Pedestrian Bridge, and will be escorted to the cordon from there. Security screening will begin at approximately 1:45 p.m. EDT; have proof of affiliation and two forms of photo identification. Journalists with a Pentagon facility access card, and whom have entered the building prior to 1:30 p.m. EDT, may go through security screening at the River Entrance to obtain their wristband. All journalists wishing to cover the honor cordon, including those with a Pentagon facility access card, must be in place no later than 2:15 p.m. EDT. Once security screening has been initiated at the base of the bridge, all journalists entering the building via the bridge for any reason, including those with a Pen
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Editor’s Note: Julian Zelizer is a history and public affairs professor at Princeton University, editor of “The Presidency of Barack Obama: A First Historical Assessment” and co-host of the “Politics & Polls” podcast. Follow him on Twitter: @julianzelizer. The opinions expressed in this commentary are those of the author. View more opinion articles on CNN.

CNN —  

Speaking at Sen. John McCain’s memorial at Washington National Cathedral, Barack Obama and George W. Bush reminded us what American presidents can sound like in times of sorrow and grief.

For younger Americans whose first real political memory of the White House is President Donald Trump, the remarks of two former presidents offered an important moment that allows us to imagine the kind of decorum and ethos that is possible when the commander in chief understands the gravity of his role.

One of the jobs of the modern presidency is ceremonial, namely to serve as consoler in chief. President Lyndon Johnson helped the nation grieve after the assassination of John F. Kennedy in 1963. “Let us continue,” LBJ told the country.

Few Americans who lived through the 1980s can forget President Ronald Reagan’s moving speech after the space shuttle Challenger exploded in 1986. “I know it is hard to understand, but sometimes painful things like this happen. … It’s all part of taking a chance and expanding man’s horizons. The future doesn’t belong to the fainthearted; it belongs to the brave.”

President Bill Clinton had just the right words to say after the horrific bombing of a government building in Oklahoma City, while President George W. Bush stirred the nation, standing at Ground Zero with first responders after the September 11 attacks.

More recently, President Obama led mourners, and the nation, through a powerful rendition of “Amazing Grace” in Charleston, South Carolina, at the funeral for state Sen. Clementa Pinckney, a pastor killed in the church massacre committed by Dylann Roof.

In 2018, we don’t have a president capable or interested in this function. President Trump handled the entire week since McCain’s death in horrendous fashion, refusing to show empathy, raising the White House flags back up from half-staff shortly after McCain’s death – lowering them again only after public outcry – and doing as little as possible to show that he cares.

As the funeral began Saturday, President Trump chose to use his time sending out tweets and retweets about the Russia investigation. During McCain’s service, Trump tweeted that NAFTA “was one of the WORST Trade Deals ever made.” Some might say that President Trump has a tin ear about how his actions come across. Others might say that it is really about having the coldest of hearts.

But, fortunately, for a moment today, the nation saw what a president can do in times like these. George W. Bush and Barack Obama, each of whom experienced some tough battles with the senator on the campaign trail, offered important words to commemorate this fallen public servant.

“Some lives are so vivid it is difficult to imagine them ended,” Bush said. He admitted that McCain “made him better” despite their tensions and frustration. He described McCain as a man with a code of values – someone who always recognized that his political opponents were still “patriots.” Bush reminded the nation that McCain did not tolerate “bigots and swaggering despots,” or leaders who acted like schoolyard bullies.

“America is better than this,” Bush pointedly remarked, remembering what McCain would say when we didn’t live up to principle.

Obama continued with another display of what it means to be presidential. We celebrate a “warrior, a statesman, a patriot,” Obama said, who embodied what was “best” of America.

When McCain spoke of “virtues like service and duty” they did “not ring hollow.” McCain forced us, he said, to think about what were “we doing for our country.” McCain understood that “some principles transcend politics; that some values transcend party.” He fought for those principles and values, Obama said. “John understood, as JFK understood, as Ronald Reagan understood, that part of what makes our country is great is that our membership is not based on our bloodline” but “on adherence to a common creed. That all of us are created equal.”

Obama reminded everyone that McCain never treated people differently because of their race, their religion and their gender, never accepting the “birthers” who challenged Obama’s legitimacy. McCain, Obama said, understood the great responsibility that came with power – that the United States guides the world through its values, not just its political might.

In stirring words, Obama explained that McCain called on the nation to be better and bigger than “politics that pretends to be brave and tough but in fact is borne in fear.” We need to follow his example.

Too often, we risk normalizing the way that President Trump acts. The nation and its politicians – Democrats and Republicans – can’t afford to do so. That is Sen. McCain’s departing message to the democracy that he loved.

As we remember a public servant who devoted his entire life to our nation, two former presidents have reminded us what it means to be president. And McCain’s memory this week reminded us about the values to which our politics must aspire. Putting aside the partisanship, there are certain norms and certain traditions that we must uphold, for those are what allow leaders to lead in crisis and sadness.