Obama highlights country's challenges; McCain hails Iran's opposition

Washington (AP)  -- President Barack Obama is blending his domestic efforts with the July Fourth holiday in his weekly address.

Obama says the "unyielding spirit" that's been present throughout our history is being called upon again. He says the nation is facing challenges "on a scale unseen in our time." And he says the economy the nation itself are "endangered by festering problems we have kicked down the road for far too long."

Obama says among the top priorities are revamping the education system, overhauling health care, and making clean energy profitable.

Obama's radio address:     

The Republican response is by Arizona Republican John McCain, who's choosing to talk about the political turmoil in Iran.

McCain says the U.S. has a moral obligation to publicly denounce the Iranian government, and support Iranians who feel cheated by their recent presidential election.