President Obama has done a lot of political living since he stood on stage at the 2004 Democratic National Convention and told the assembled masses that there were no red states or blue states just the United States of America.

President Obama speaks on the 50th anniversary of the March on Washington. EPA.

But, in a speech Wednesday commemorating the 50th anniversary of the March on Washington, Obama returned to those rhetorical roots -- tying the fight for equal treatment of African Americans to fights for equal recognition of gay Americans, those with disabilities and many other groups that have fought for their civil rights.

Here's the key passage:

"We must remind ourselves that the measure of progress for those who marched 50 years ago was not merely how many blacks had joined the ranks of millionaires; it was whether this country would admit all people who were willing to work hard, regardless of race, into the ranks of a middle-class life. The test was not and never has been whether the doors of opportunity are cracked a bit wider for a few. It was whether our economic system provides a fair shot for the many, for the black custodian and the white steelworker, the immigrant dishwasher and the Native American veteran. To win that battle, to answer that call -- this remains our great unfinished business."

That is essentially the same frame -- and same challenge to the country -- that Obama laid out nine years ago when he went from an unknown state senator to a national figure.

"People don't expect -- people don't expect government to solve all their problems," Obama said then. "But they sense, deep in their bones, that with just a slight change in priorities, we can make sure that every child in America has a decent shot at life and that the doors of opportunity remain open to all. They know we can do better. And they want that choice."

Obama allies will note -- as David Axelrod did in a tweet soon after the speech -- that the President continues to return to those themes because they are what have "animated his entire public life" in Axelrod's words. Despite the slings and arrows, despite the setbacks -- many of which Obama advisers blame entirely on Republicans -- this is a man who still believes what he believed a decade ago: That the country is not so divided as people think and that our common values are what can bring us together -- if only we could recognize that we share them.

His critics will push back that the nine years since Obama gave that first major speech has shown him far less willing to walk the walk than talk the talk. What in 2004 appeared to be a promise of a different kind of politics has turned into the same old politics nine years on -- with an emphasis on vilifying Republicans rather than finding ways to work with them.

The truth? It's impossible for Obama to jump in the time machine and re-create the circumstances that surrounded that 2004 address. He's older now and, as the 2012 election showed, has a much more practical approach to how politics works (and can work) in Washington.

Obama still believes in his vision of common values and moving beyond partisanship. But, as the last nine years has shown, changing Washington -- and the broader partisan country in which we live  -- is easier said than done.