Taking America going to Iraq war, it might be a disturbing fact, but America wanted to go at war back then. The bloodlust of a common, red-blooded, mall-shopping American in the wake of 9/11 is the foremost reason the U.S. ended in two prolonged conflicts. Yes the reasons for Iraq were pulled from the hat, but the nation was eager to be deluded. Not a conspiracy of two men in DC: can anyone really imagine the USA not invading anyone after the 9/11 attacks?
But again what's happening here is that in democracy, the influences become averaged with certain cut-off of extremes, like a signal through a band filter. The politics becomes statistical, as opposed to heuristic deal in feudal countries like North Korea, and as such becomes harder to disrupt.