The National Civil Rights Museum sits in what was the Lorraine Motel, just beyond the shadows of Memphis's skyscrapers and the garish neon glow of Beale Street - the main drag made famous by the likes of BB King and James Baldwin. The first words of the first exhibit state: "Protest against injustice is deeply rooted in the African-American experience." Then come pictures of lynchings, burning crosses, martyrs and heroes, alongside mock-ups of Rosa Parks in the bus and lunch counters waiting to be integrated.

"The way we see things is affected by what we know and what we believe," wrote John Berger in

Some will wonder in years to come how, with markets wavering, the Fed ready to pronounce and the American economy flirting with stagflation - or, worse still, recession - the top political story in the US became a story about race, even for a few hours. Not even a story. A speech. A good speech - a speech that could have been delivered any time over the past 30 years, but also, somehow, had to be delivered now.

In years to come some will wonder how, with markets wavering, the Fed ready to pronounce and the US economy flirting with stagflation or, worse still, depression, the top political story in the US became a story about race - even for a few hours. Not even a story - a speech. A good speech. But nonetheless a speech that both could have been delivered any time over the past 30 years and also, somehow, had to be delivered now.

During his 1984 presidential bid Jesse Jackson vowed to choose a woman as his running mate - the only candidate to do so during the primaries. Having drawn in a new cohort of voters, he mobilised the "rainbow coalition" of blacks, Latinos, trade unionists, feminists, peace activists and gays to mount a credible challenge to the Democratic party establishment. Originally treated as a fringe candidate, he came in third with 20% of the vote. So even as the party sought to sideline him as an individual, they knew that he had awakened a constituency whose demands they would have to engage with.

On the night when Barack Obama took Virginia, Maryland and Washington DC with 20 point leads, an equally potent primary result came in from Maryland's fourth congressional district. Away from the glare of the international media, Donna Edwards, anti-war campaigner and community activist, trounced eight-time incumbent Albert Wynn in the battle for the Democratic nomination. This was no minor achievement. A sitting congressman had not been ousted in a primary in Maryland for 16 years. In 2006, a high tide for anti-incumbent sentiment, Edwards lost to Wynn by 3%. But she persevered. Wynn had taken huge sums from lobbyists. He had voted for the Iraq war, Dick Cheney's energy bill and to repeal inheritance tax. Edwards argued that this was against the wishes and interests of his mostly black, middle-class constituents. Last month she beat him by 35%.