There are two types of people: those whose careers find them and those who map their path with brisk determination. Lonnie Bunch, 52, who was appointed the director of the Smithsonian Institution's National Museum of African American History and Culture in 2005, slips snugly into the latter category.

Bunch has been on an ambitious mission throughout his almost 30-year museum career. And he perhaps faces his biggest challenge so far as he begins to lay plans for the yet-to-be-built National Museum of African American History and Culture on the Washington DC Mall.

Bunch is and has always been concerned with pushing the African-American experience in its entirety to the mainstream. But his goal is much deeper than this. He wants the historical African-American experience to inform what it is to be an American. In other words, he wants everyone in the US to understand that their identity has been affected by the struggle of African-Americans.

'Regardless of when your family arrived [in America], it is the African-American experience that is shaping the experience of citizenship. I want everybody to suddenly see that this is [them],' he says.

Bunch grew up in New Jersey and was always curious about the local museum, despite being 'waved away' by a member of staff. But still: 'I felt there was something crucial in the museum for me to see.'

He attended Howard University, the leading African-American institution, which he says 'gave us access to scholarship of race and its questions and embedded in us that the story of race is crucial to the US'.

He was also profoundly moved by a quote from Carter G Woodson, the originator of the 1920s US Negro History Week (later to become Black History Month): 'The only reason I do history is to make America better.'

For Bunch, a museum about African-American history and culture on the mall is something that will make America better. 'This is not a museum of black history for black Americans,' says Bunch. It's to tell the quintessential story of American history to all Americans.

The Museum of African American History and Culture is likely to be the last to be built on the coveted mall and as such has generated a flurry of interest. Bunch wants an open and inclusive design competition for the building, which will give all sections of the international community, including Africa, a fair shot, he says.

Remarkably, the museum has been almost a century in the making. The 50th anniversary of the battle of Gettysburg took place in 1913 and celebrations brought together Union and Confederate soldiers, symbolising that the country had healed.

But African-Americans were barred from participating although they had also fought in the civil war. Bunch says that this led to a struggle as early as 1916 to get a museum of African-American culture on the mall. In the late 1920s the president signed a bill saying there should be such a museum. But then the Depression happened and later civil rights campaigning took over.

Bunch believes that it is becoming a reality now because there is about 30 years of real scholarship to be employed; and he says republicans and democrats are behind the effort. The strength of a burgeoning black middle class with money to support the venture has not gone unnoticed.

Television celebrity Oprah Winfrey has been co-opted onto the museum board along with other entertainers and leading black business figures. Money, as well as the expected kudos, is a likely outcome, and Bunch is enthused by it: 'With this board', says Bunch, the museum 'is more than do-able'.

The cost of the museum is expected to be $300m. Bunch says millions of dollars have already been raised, some coming from foundations and individuals. In the Smithsonian tradition, Congress is expected to pay 50 per cent of the cost of the building - making it an equal partner along with the federal government, which will pay for staffing.

Bunch says the major four-year fundraising campaign is about to get underway. Although the latest museums to open on the Washington mall took 15 years (the National Museum of the American Indian) and 14 years (the Holocaust museum) to open, Bunch promises his will be open in eight.

Despite the lack of a physical space and a collection, Bunch says the museum already exists. Touring exhibitions are to be launched this year alongside a 'massive' interactive educational website.

And what, where and how will the museum collect? Bunch says this is 'one of the many things that makes me wake up at 2 o'clock in the morning'. There is every intention for the museum to be artefact-rich.

The museum will cover the struggle of black America - slavery, civil rights - but also its strength in overcoming the obstacles. The museum's goal is to help the public remember, says Bunch. It will tell the familiar stories of well-known figures such as Frederick Douglass and Rosa Parks.

But he also aims to tell of 'the average slave who refused to let the field break their humanity'. He wants to show the 'richness and complexity' of the African-American story. 'I don't want to create a black Holocaust museum, but I want you to cry,' he says.

The visitor experience will be a cultural one too. He wants people to 'tap their toe' to Louis Armstrong or Duke Ellington. He envisages arts and performing theatre to be an integral part and wants an African-American film festival to take place there each year.

Bunch argues the African-American experience is the best way to understand the core values of America - optimism and equality. African-American culture, if Bunch has his way, will be understood in a far deeper way than it is today. 'Far too often African-American history is seen as exotic and ancillary,' he says.

The Smithsonian represents 'America's front porch. It's the place you go to understand American art, culture and history.' He is banking on the 4 million people that he says will be attracted to it because of its institutional brand.

The Smithsonian only has 30 per cent of the artefacts needed. Bunch says the museum will put out a call for a national collecting initiative to save African-American heritage. He believes all the 20th-century artefacts are in people's homes.

He wants to make curators and conservators available to go into homes to preserve the artefacts. Any bequests will go to regional museums. 'It's not about collecting, it's about preserving,' says Bunch.

Bunch's track record shows he has the will and the way to succeed in the challenge ahead. He is already well versed in the ways of the Smithsonian having worked as assistant director and then associate director for curatorial affairs at the National Museum of American History (1992-2000).

He led the curatorial team and developed major permanent exhibitions, as well as supervising the planning and implementation of the museum's research and collection agendas. Between 1978 and 1979 he was an education specialist at the Smithsonian's National Air and Space Museum and developed its learning programmes.

Early on in his career he held the deputy director position at the California Afro-American Museum; he says at the time he 'was too young and too dumb' to know what a big task he was taking on. He also produced several historical documentaries for television.

But he really made his mark as president of the Chicago Historical Society (2001-2005) where he led a successful capital campaign to transform the institution for its 150th anniversary while managing an organisational review.

In such a racially divided city (he said he took the job because it was about the greater good) he initiated an outreach programme to diverse communities. He says there's a saying in America that '[as an African-American] you have to be twice as good to get half as far'.

He said he knew he had to be a good historian but unlike some of his colleagues, he realised early on that he also needed to pay attention to audiences because he would need their support. Indeed, during his time at the American history museum he recalls being mistaken for the elevator operator.

'That has been something that has really made sure I remain connected to my community,' he says. He says he also 'had to learn how to be a good manager and how to work the system politically and financially'.

When I meet Bunch with his wife for a breakfast interview at the Langham Hotel on London's Regent Street, I can see he is a savvy operator. He also appears to be popular, always smiling, and always gracious and clever.

What is gratifying is that Bunch hasn't forgotten where he has come from and the ability he now has to help others. 'On the one hand, [the museum] profession says we believe in inclusion. But on the other hand, it has been pretty miserable in terms of the numbers.' And he is bent on using his position to 'open windows' for others so he is 'not seen as the great exception'.