The five living former presidents all appeared together for the first time since 2013 at a concert on Saturday to raise cash for victims of devastating hurricanes in Texas, Florida, Louisiana, Puerto Rico and the US Virgin Islands.
Democrats Barack Obama, Bill Clinton and Jimmy Carter and Republicans George H.W. and George W. Bush gathered in College Station, Texas, in a bid to unite the country in compassion.
President Donald Trump appeared via a video greeting in which he avoided his previous criticism of the former presidents and called them "some of America's finest public servants."
"This wonderful effort reminds us that we truly are one nation under God, all unified by our values and devotion to one another," Trump said in the greeting, played during the concert.
Grammy award winner Lady Gaga made a surprise appearance at the concert that also featured country music band Alabama, 'Soul Man' Sam Moore, gospel legend Yolanda Adams and Texas musicians Lyle Lovett and Robert Earl Keen.
The appeal backed by the ex-presidents has raised $31 million since it began on September 7, said Jim McGrath, spokesman for George H.W. Bush.
Four of the five former presidents - Obama, George W. Bush, Carter and Clinton - made brief remarks that did not mention Trump. The elder Bush, now 93 and suffering from a form of Parkinson's disease, did not speak but smiled and waved to the crowd.
"The heart of America, without regard to race or religion or political party, is greater than our problems," said Clinton.
The last time the five were together was in 2013, when Obama was still in office, at the dedication of George W. Bush's presidential library in Dallas.
There is precedent for former presidents joining forces for post-disaster fundraising. George H.W. Bush and Bill Clinton raised money together after the 2004 South Asia tsunami and Hurricane Katrina the next year. Clinton and George W. Bush combined to seek donations after Haiti's 2011 earthquake.
Hurricane Harvey slammed into Texas and Louisiana Gulf Coast as a Category 4 hurricane on August 25, unleashing historic flooding in Houston and killing more than 80 people.
Shortly thereafter, all five ex-presidents appeared in a commercial for a fundraising effort known as "One America Appeal." In it, George W. Bush says, "People are hurting down here." His father, George H.W. Bush, then replies, "We love you, Texas."
Hurricane Irma subsequently hit Florida and Hurricane Maria battered Puerto Rico, while both devastated the US Virgin Islands.
Amid criticism that his administration was initially slow to aid ravaged Puerto Rico, Trump accused island leaders of "poor leadership," and later tweeted that, "Electric and all infrastructure was disaster before hurricanes" while saying that Federal Emergency Management Agency, first-responders and military personnel wouldn't be able to stay there forever.
A website accepting donations, OneAmericaAppeal.org, has been created with 100 per cent of proceeds pledged to hurricane relief.