Iraq: Why?

Indeed, just as America's enemies would love to know every American troop movement and battle plan, so would the jihadist foe also like to know why the United States is in Iraq at all. Is it a secret plan to lull the enemy into a false sense of winning? A grand plan to spread freedom in the form of militant Islamism? Is it all a massive fake out, a "look at Iraaaa... whooops, got yer Syria"? Is the entire War On Terror merely a front for a larger, grander, even nobler War On Something Else (War On Tyranny, War On Evil, War On War, War On Stuff)?

As usual, The Medium Lobster knows, but if he told you...well, you know the drill.