While Russian diplomats undertake to safeguard humanitarian access, in accordance with last week’s agreement in Munich, their warplanes turn undertakers. Three clinics and a school sheltering the displaced were bombed yesterday, including a Médecins Sans Frontières hospital in Idlib province. Reports from Aleppo, Syria’s second city, say air strikes have increased by 50% since the Munich deal, to over 100 a day. Firepower is concentrated on the road from rebel-held northern Aleppo to Turkey, which the Russians explicitly promised to protect. To Turkish ire, Russia is also providing air cover for Kurdish forces, notably those attacking Azaz, 7km (five miles) from the border. Planes are hitting southern Syria, too, where Bashar al-Assad’s regime is fighting to regain the crossing into Jordan. Russia may just be firming up Mr Assad’s line of control before the ceasefire scheduled for Thursday. To Syrians, the diplomacy looks like a fig-leaf for the regime’s and the Russians’ advance.