Former US President Barack Obama, celebrating a new museum and civic centre dedicated to his eight years in the White House, called on Americans to resist the forces of political cynicism ​and division and instead embrace "our shared responsibilities as citizens."The 44th US president, who left office nearly a decade ago, led a crowd of thousands on Thursday attending a music-filled grand opening of the Obama Presidential Center, ‌a lakefront Chicago campus of granite, nature and art honoring and archiving his administration.He was joined by his wife, former first lady Michelle Obama, and a list of dignitaries that included three other former US presidents, several foreign heads of state and a cluster of A-list recording artists, among them Stevie Wonder and Bruce Springsteen.The US$850 million (NZ$1.44b) landmark development, which opens to the public on Friday (local time), ranks as the greatest single investment in a century for Chicago's long-neglected South Side, where the Obamas were married and made their family's home.The sprawling museum complex, encompassing a performing arts hall, library and athletic centre, ​was designed to cement the legacy of Obama's two terms in the White House and to serve as a hub of civic life and culture on the banks of Lake Michigan.In separate speeches they delivered on Thursday, Barack and ​Michelle Obama also pointed to the museum as a symbol of democratic ideals they contrasted with the rancor and upheaval pervading US politics under President Donald Trump, whose name was mentioned ⁠by neither of the Obamas.'Grace and class and cool'"A lasting legacy isn't in a war, or a name on a building or the number of zeros in a bank account, it's about the difference we make in one another's lives," Michelle Obama said, ​pointedly noting her husband as a Nobel Peace Prize recipient and praising him for his "stubborn optimism.""With grace and class and cool, you made the hardest job in the world look like a walk in this beautiful park," she said in a tribute that visibly ​brought her husband to tears.Taking the stage a short time later, the former president acknowledged that "appeals to democracy and civic participation" may seem "old-fashioned" and "naive" when "the future feels uncertain, the ground unstable beneath our feet."But he urged Americans not to lose faith in their nation's founding principles of equality and self-government."I hope this centre will serve as an affirmation of just how special, how precious, our democracy truly is, and remind us what we can achieve when we embrace our shared responsibilities as citizens," he said.By giving up on citizenship, Obama warned, "we open the door to the most ruthless, or the ​most careless, or the most fearful among us, who see some people and some groups as more equal than others, and see government as nothing more than a way to divvy up the spoils and punish enemies and keep those who are different ​in their place"."I do not believe that is the story of America that prevails in the end," he added to applause.US singer-songwriters Bruce Springsteen (L) and Eddie Vedder (R) perform during opening day of the Barack Obama Presidential Center.KAMIL KRZACZYNSKI / AFPFormer presidents attend ceremonyThe Obamas were joined at the event by their two daughters, Malia and Sasha, and three other living former occupants of the Oval Office - ‌former presidents Bill ⁠Clinton, George W. Bush and Joe Biden - and their wives, former Secretary of State Hillary Clinton, Laura Bush and Jill Biden.The list of VIPs who attended also included former Vice President Kamala Harris and her spouse, Douglas Emhoff, former US House Speaker Nancy Pelosi and such foreign dignitaries as former German Chancellor Angela Merkel and former Canadian Prime Minister Justin Trudeau.Among the Grammy-winning musical stars who performed during the three-hour ceremony were hip-hop group the Roots, Jennifer Hudson, John Legend, Common, Eddie Vedder and U2's Bono and the Edge. Springsteen and Wonder rounded out the musical program following Obama's keynote speech.Apart from the throng of invited guests at the centre itself, a crowd of thousands more ticketed spectators watched the ceremony on a big screen from another park near the centre. The proceedings ​were also carried on a global livestream.The Obama Center, occupying ​19.3 acres of historic Jackson Park, is an ambitious blend ⁠of landscaping and architecture encompassing such elements as a playground, gardens, a concert hall and NBA-sized basketball court.'Bombastic and beautiful'Organisers have said they expect the Obama Center to draw 750,000 to 1 million visitors a year. Money for the centre was raised privately through the former first couple's Chicago-based nonprofit Obama Foundation.The centrepiece is a museum devoted to Obama's personal story and his two terms ​as president, from 2009 to 2017. The design of the museum, an eight-story, irregularly shaped granite-clad tower, has drawn mixed reviews in a city renowned for bold and varied architecture. It ​already has been nicknamed the Obamalisk, ⁠but also has been described as evoking the shape of four hands coming together and reaching upward."I find it really striking and bombastic and beautiful in the best possible way," T Camille Martin-Thomsen, a professor of architecture and the dean of faculty at the School of the Art Institute of Chicago, said of the museum tower.Other major components of the site include a Great Lawn for casual summer picnics and winter sledding; a new branch of the Chicago Public Library; an outdoor plaza honoring late civil rights leader and US lawmaker John Lewis; ⁠an athletic centre ​dubbed Home Court; and a multimedia performance and programming space called the Forum.The campus also features 28 original artworks. A network of interconnecting pathways, gardens ​and green space planted with 900 native trees is open to adjacent park land.After Thursday's event, Sarah Day, a former Obama campaign staffer who traveled from Salt Lake City for the dedication, said the former president's speech invigorated her, and also made her emotional."It's really hitting home that we can't give up, we can't ​be tired," she said. "Democracy is hard, but we need to keep working."- Reuters