Saddam did his best to suggest he still had WMDs after GW1 and used them in the past vs the Kurds and Iranians, IIRC. The evidence was pretty convincing to most involved, to the point that allied intel agencies believed he had them. Unless GWB had information not yet uncovered, it is more plausible that he believed Saddam had WMD than GWD made it up and lied about the issue. When WMDs were not found immediately afterwards, GWB made a mistake in conceding the point as later were found both the capacity to restart WMD production and existing stockpiles.
Saddam was a credible threat to Jordan, Kuwait, Syria, and maybe the Saudis. He could not touch the USA save by terrorism and the Iranians were too strong for him to take on after GW1. I am sure the usual neo-neo-con(1) folks could argue that this was a threat to America. A bit of a stretch.
(1) As opposed to the old neo-cons of course being the Jewish Trotskyites who were born again anti-commie and pro-Israel. The Neo-neo-cons being those who came along later and seem to want to invade the world with our troops while inviting the world to replace those descended from America's founding culture and population.