Biden says US troop withdrawal from Afghanistan not yet done

The US has pulled its troops out of Bagram, a vast complex north of the Afghan capital, Kabul. It's served as the hub of US-led operations for almost two decades. We hear from a retired US Army colonel who served in Afghanistan and from a young Afghan student. Also in the programme: is hydrogen a realistic source of green energy? And power cuts leave Iraqis at the mercy of soaring temperatures and prompt a series of high level resignations. Photo: An Afghan soldier stands guard at a checkpoint near Bagram air base, on the day the last of American troops withdrew from it. Credit: Reuters/Mohammad Ismail