There is a knee-jerk reaction among many northerners and suburbanites to the southern heritage crowd that wraps itself in the confederate battle flag -- "The war is over, you lost." Sometimes it is modified by the length of time since the war (120, 150 years, depending on the decade). But it is always wrong.
As I wrote as much in a comment on the esteemed Kevin Levin's article, but I'd like to expand my thoughts here.
As the Comedian Louis CK says 150 years is 'two old ladies back-to-back' -- there are many African Americans alive today whose grandparents were slaves. Beyond abandoning our history to those who celebrate treason, merely moving on minimizes the closesness of the War and how much of the inequality from slavery remains in our society.
I prefer to celebrate the sacrifice of those loyal to the US and to celebrate their accomplishment, rather than just suggesting that the whole affair doesn't matter.
On the other hand, as a descendent of Confederate soldiers and slaveholders (on one side, union soldiers are on the other) I feel like southerners have a duty to wrestle with our past and where we come from (see Faulkner, William). Confronting the ugliness that we find will help southerners understand the South as it is today and to make it better.
I think that the whole-hearted engagement with our past is the only way to counter those who would celebrate our nation's dismemberment.