As the war in Iraq seems to be continuing with no end in sight, comparisons have increasingly been made with the US experience in Vietnam.
Many of the same questions asked then are being asked again now.
When will the conflict end? Has the United States got itself stuck in another quagmire? Is the war in Iraq winnable at all?
Not everyone, however welcomes these comparisons.
Part One - Past and present compared?
In the programme - the first of a two part series - our Diplomatic Correspondent Jonathan Marcus compares the impact of the two conflicts on American society and politics.
It seems that the parallel between the two wars is being used in campaigns of a few presidential candidates.
What does this all mean for the upcoming presidential elections?