It’s been a year since Bradley Manning was arrested for allegedly handing over a half million classified documents to WikiLeaks, in the biggest intelligence breach in U.S. history. The former Army intelligence analyst remains jailed in the Army brig in Fort Leavenworth, Kansas, awaiting his first pre-trial hearing, while WikiLeak’s head Julian Assange lives under police watch in a home near London. Their relationship is the focus of a Frontline documentary "WikiSecrets," airing tonight. Bradley Manning’s father Brian Manning says his son is innocent. He joins Frontline correspondent Martin Smith to discuss his son and the documentary.

A recent report by the College Board found students at for-profit colleges graduated with significantly more debt than their counterparts at public and private non-profit schools. President Obama recently overhauled the federal student loan program, changing the landscape for college lenders. Now Congress is considering ways to increase oversight of these for-profit colleges, which receive significant amounts of federal financial aid.

The photo of the flag raisers on Iwo Jima has long been an emblem of U.S. efforts in World War II; photos from My Lai still represent the Vietnam war for many. After eight years, however, there is still no single image that has defined the Afghan war. A new PBS/Frontline documentary, "Obama's War," contains footage and images of the war that hasn't been seen on American television screens until now.

The film begins with the death of a U.S. marine, Lance Corporal Seth Sharp, who is cut down by Taliban fire during a battle in Helmand province last summer. We speak with Seth's father, Ric Sharp, and Danfung Dennis, the photojournalist who captured the footage, about the power of images in the Afghan war. Martin Smith, co-director of "Obama's War," also joins us.

[Watch the first 24 minutes of the film here, or visit Frontline's website this evening for the entire piece.]