The order came from Rumsfeld, not Bush, in a memo in October. Rumsfeld had dropped the use of the term months before, so it's unlikely that he was ordered to formally drop it, more likely that he nagged until he got permission to do so.
He also disliked the phrase National Command Authority (NCA) and has insisted that it be dropped in favour of naming the post, e.g. the president, secretary of state etc.
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