(Nature) – As the world this week commemorates the armistice that ended the First World War in 1918, it is reprehensible that humanitarian rules forged in the suffering and bloodshed of battle are often being violated in contemporary conflicts. In the past month alone, two hospitals run by Médecins Sans Frontières (MSF; also known as Doctors Without Borders) were hit by air strikes. US warplanes destroyed one in Kunduz in Afghanistan — killing 13 MSF staff and 17 others — and another in Yemen was targeted, allegedly by Saudi-led coalition forces.