This (along with striving to get good PR) is one of the main reasons the US government is so keen to redefine the word "torture" to mean something that they don't do. The same goes for the words "terrorism" and "terror".

  "Shock and awe" == good
  "Terror" == bad

  "Torture" == illegal
  "Stress position" == legal

  decapitation with a knife == horrific and evil
  decapitation by shrapnel == worthy of a medal

  assassination by the American govt == good
  assassination by other governments == bad

  killing by poison gas on the battlefield == bad
  killing by poison injections in a prison == good