If anyone says it was about "regime change" then they are admitting to an agressive war and open their government up to war crime charges - so NO it was NOT actually or tacitly seen as the reason for the war - it was constantly denied by both US and UK governments.
Now what Bush's and others' actual reasons really were, no one knows - but the real reason "regime change" caught on was to try to excuse the complete mess they made of the occupation/nation building.
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