In the shadow of Philadelphia’s Independence Hall, Sen. Barack Obama (D-Ill.) sought Tuesday to free himself from lingering questions over the “complexities of race” in the United States and in his presidential campaign.

Obama gave a speech, titled “A More Perfect Union,” at Philadelphia’s National Constitution Center on identity politics and racial divisions in America — issues he said “must be addressed.”

The speech came in the wake of mounting unease about Obama’s former pastor, Rev. Jeremiah Wright, who has made comments some have perceived as racially divisive and anti-American. In one sermon, Rev. Wright proclaimed, “God damn America for killing innocent people.”

Wright also criticized Sen. Hillary Clinton (D-N.Y.), Obama’s opponent for the Democratic presidential nomination, as naive to think she can empathize with black Americans.

While Obama rejected Wright’s statements as “incendiary language” that would “rightly offend white and black alike,” he also explained Wright’s comments in the context of America’s ongoing racial divide.