What Was Different Between the Vietnam War and the War

What was different between the Vietnam War and the war in Iraq that made a comparison between the two not a perfect application of history?

A) Unlike Vietnam, the conflict in Iraq was a short war.
B) Unlike in Vietnam, the United States engaged in state-building in Iraq.
C) Unlike Vietnam, American domestic support never waned in the Iraq War.
D) Unlike Vietnam, the conflict in Iraq involves competing ethnic groups' self-interest.
E) Unlike Vietnam, the Iraq War is not considered a quagmire.