(2) We un-destroyed it. AKA "Libertated".
(3) They were working on WMD, had some, and more importantly they showed inclinations towards their use, and indeed have used them.
(4) We are not trying to "save the world" -- we are required to protect ourselves. In Afghanistan, in Yemen, in Pakistan, and in Iraq we have taken steps small and big to protect ourselves.
(5) That oil was being used to fund terror in the world and desolation of the people of Iraq. Better Harborton own the fields, the oil and the profit. Harborton isn't in business of killing and impoverishing for the sake of power. Saddam was. The Saudi's -- they still are. Hooray for US Oil Barons! They are gentleman and scholars compared to the terror-breeding rats who own and profit many thrid world fields.
Oh and don't be such a Zot attracting bug, eh?