Breaking ground on the new Smithsonian National Museum of African American History and Culture, President Obama said today he hopes the museum will remind future generations of the "sometimes difficult, often inspirational, but always central role that African-Americans have played in the life of our country."

The president spoke of what he would like his own two daughters to take away from the long-sought-after museum, which will be the only national museum devoted exclusively to African-American life, art and history.

"I want my daughters to see the shackles that bound slaves on their voyage across the ocean and the shards of glass that flew from the 16th Street Baptist Church and understand that injustice and evil exist in the world, but I also want them to hear Louie Armstrong's horn and learn about the Negro League and read the poems of Phillis Wheatley," he said. "I want them to appreciate this museum not just as a record of tragedy but as a celebration of life."

The president was joined by his wife, Michelle Obama, and former first lady Laura Bush at today's ceremony. The museum, which is set to open in 2015, will be built between the Washington Monument and the National Museum of American History.

Obama said it was fitting that the museum have a place on the National Mall. "It was on this ground long ago that lives were once traded, where hundreds of thousands once marched for jobs and for freedom. It was here that the pillars of our democracy were built often by black hands," Obama said.

"What we build here won't just be an achievement for our time; it will be a monument for all time," the president said. "This museum … should stand as proof that the most important things in life rarely come quickly or easily. It should remind us that although we have yet to reach the mountaintop, we cannot stop climbing."