First: I wasn't trying to equate them, I was simply trying to point out that the question, as asked, was not sufficient to make the point I believed the poster was intending to make. And I certainly think that WW II in Europe
*was* similar. Germany and Italy were no direct threat to the US but our allies were either overrun (happily avoided by allied intervention against Iraq by GHW Bush) or in danger of attack by mad despots who were killling and/ or imprisoning thousands or millions of their own people. World powers don't necessarily react only to direct threats to themselves (which is the point of organizations like NATO, although NATO itself is not otherwise relevant to my point). And, still, your blanket statement that Iraq under Hussein was not a threat to the US is not universally accepted (WMD and the possibility of their falling into the hands of terrorists, Iraqi interference with US attempts to verify and enforce the conditions that ended the first Gulf war).Sure, now that the real work, getting rid of the Ba'athists, is done. Many knowledgeable Iraqis who do not viscerally oppose allied presence just because we are us and who understand the current state of Iraqi readiness to defend itself and its people are happy we're there. As are a significant number of Kuwaitis, Israelis and no doubt other members of the governments, militaries and general population of Iraq's neighbors.
Terrorists existed and were acting against Americans and allies well before we were embroiled in Iraq. And I disagree with the notion that the US should necessarily ignore the evils of one despot to hold another in check, that is just one more element to include among those bearing on the decision. Also, you forgot to mention Afghanistan; I assume you deliberately excluded North Korea because of geography. :)