The year 2011 will go down in history as one which saw America's second-longest war officially come to an end.

"There are different types of war … including wars where foreign invaders come in and who are culturally, linguistically and historically illiterate; unable to speak the language or communicate with those they are occupying other than through the language of force are always the dirtiest types of wars."

- Chris Hedges, war correspondent

Barack Obama, the US president, said US troops can leave Iraq with "their heads held high", but for some, it is not that easy.

Now that the troops are home, Inside Story Americas examines their experiences, and the lessons and legacy of the Iraq war.

So, what lessons did US troops learn in Iraq? And have they returned home to a country receptive to their experiences?

Inside Story Americas, with presenter Shihab Rattansi, discusses with this week's guests: Ross Caputi, a former US marine who wrote "I am sorry for the role I played in Fallujah" for the Guardian newspaper; Chris Hedges; a war correspondent and co-author of the book "Collateral Damage: America's War Against Iraqi Civilians"; and Manal Omar, an aid worker in Iraq during the war and the director of the Iraq and Iran programme at the US Institute of Peace.

"I don't think anyone in my unit ever would have condoned doing to their own family, it was completely brutal. I think [what we were told] was coherent but it was a lie. We destroyed their houses [in Fallujah], we destroyed their lives."

Ross Caputi, former US marine

Source: Al Jazeera