Colonel Richard Kemp, former Commander of British Forces in Afghanistan, spoke in 2011 about Israeli operations in the Gaza War. He said that a study published by the United Nations showed "that the ratio of civilian to combatant deaths in Gaza was by far the lowest in any asymmetric conflict in the history of warfare." He stated that this ratio was less than 1:1, and compared it favorably to the estimated ratios in NATO operations in Afghanistan (3:1), western campaigns in Iraq and Kosovo (believed to be 4:1), and the conflicts in Chechnya and Serbia (much higher than 4:1, according to anecdotal evidence). Kemp argued that the low ratio was achieved through unprecedented measures by the IDF to minimize civilian casualties, which included providing warnings to the population via telephone calls, radio broadcasts and leaflets, as well as granting pilots the discretion to abort a strike if they perceived too great a risk of civilian casualties. He also stated that the civilian casualties that did occur could be seen in light of Hamas' tactical use of Gazan civilians "as human shields, to hide behind, to stand between Israeli forces and their own fighters" and strategic use of them for exploitation of their deaths in the media.