Juxtaposed against this, I think Obama is right that we should remember our unity as fellow citizens, fellow Americans, neighbors, friends, and countrymen. As he put it in his famous DNC speech:
The pundits, the pundits like to slice-and-dice our country into Red States and Blue States; Red States for Republicans, Blue States for Democrats. But I’ve got news for them, too. We worship an "awesome God" in the Blue States, and we don’t like federal agents poking around in our libraries in the Red States. We coach Little League in the Blue States and yes, we’ve got some gay friends in the Red States. There are patriots who opposed the war in Iraq and there are patriots who supported the war in Iraq. We are one people, all of us pledging allegiance to the stars and stripes, all of us defending the United States of America.
The line about "slice-and-dice" is indicative -- it's the creation of division that he objects to. Indeed, later on in the same passage he actively concedes political division and affirms the patriotism of both those who supported and those who opposed the Iraq war. So I think it's better to read Obama's unity rhetoric not as a political agenda, but as a critique of a particular political strategy that has been dominant in American politics for quite some time now.