Answer:
The US stated that the intent was to remove "a regime that developed and used weapons of mass destruction, that harbored and supported terrorists, committed outrageous human rights abuses, and defied the just demands of the United Nations and the world. For the invasion of Iraq the rationale was "the United States relied on the authority of UN Security Council Resolutions 678 and 687 to use all necessary means to compel Iraq to comply with its international obligations".
I hope this helps a little bit.
Because people started associating violence with those unions
