We know the American war crimes in Iraq, but We may never know if the British committed war crimes there Why? Because the British forces are (almost) perfect. The last person in Britain to be prosecuted for crimes committed by forces under their command was in 1651 during the civil war.
“The West won the world not by the superiority of its ideas or values or religion (to which few members of other civilizations were converted) but rather by its superiority in applying organized violence. Westerners often forget this fact; non-Westerners never do.” —Samuel P. Huntington, The Clash of Civilisation and the Remaking of the World Order, 1996, p. 51