At 1.46pm BST on 11 September, this blog will publish two tributes to victims of 9/11. These are for Norberto Hernandez (a pastry chef in the Windows on the World restaurant) and Dwayne Collman, a flight attendant on flight 11, which crashed in Pennsylvania.
Much has changed in the world in these 15 years. Unfortunately, mindless violence has not yet left us.