NEW YORK — President Barack Obama today praised the new Sept. 11 museum as “a sacred place of healing and of hope” that captures both the story and the spirit of heroism and helpfulness that followed the attacks.

“It’s an honor to join in your memories, to recall and to reflect, but above all to reaffirm the true spirit of 9/11 — love, compassion, sacrifice — and to enshrine it forever in the heart of our nation,” he told an audience of victims’ relatives, survivors, rescuers and recovery workers at the ground zero museum’s dedication ceremony.

After viewing some of the exhibits, including a mangled fire truck and a memorial wall with photos of victims, the president touched on some of the many stories of courage amid the chaos: the passengers who stormed a hijacked plane’s cockpit over a Pennsylvania field and first responders who rushed into the burning twin towers. He also honored military members “who have served with honor in more than a decade of war.”

Before the ceremony, Obama walked quietly through an expansive hall with former New York City Mayor Michael Bloomberg. First lady Michelle Obama, former President Bill Clinton and former Secretary of State Hillary Rodham Clinton following behind them.

The museum, which commemorates the 2001 terrorist attack, as well as the 1993 World Trade Center bombing, opens to the public on May 21.