The Iraq war was based on lies purported by the Bush administration, and the cost in American human life and suffering is unconscionable. There was no good reason to go to war, and this was has cost us not "only" in life and suffering, but billions of dollars that was exhausted so stupidly could have gone a long ways toward building our own infrastructure and making our country stronger in various ways.
I still today in the year 2013 don't understand why the war in Iraq occurred. Is it to fight terrorism? Is it in the benefit of the richest and the super elite? Is it because Saddam Hussein was a dictator and the U.S had to intervene? Regardless of the motive I have still yet to receive and conclude a definite answer.
We went to war in Iraq first because the government claimed that Iraq housed those that attacked us during 9/11, and then when everyone figured out that it wasn't true the government claimed that Iraq had weapons of mass destruction. Of course, we couldn't find those, either, therefore that was a big lie. So the two main reasons we even occupied Iraq was because of a lie.
The war on Iraq was based on false intelligence, not lies, that Iraq had two things: individuals involved in 9/11 and WMD's like the Mustard gas Saddam used on the Kurds in late 1980's, which were stockpiled for decades. After our forces came in and kicked the Republic Guards' asses, the search for WMD's began. I am assure forces on the ground found sites were such weapons once stored not long ago like few months to a year or two; other sites where such weapons were being mades were found based on precursors detected and collected. On those individuals involved, like the WMD's, we knew they were there at one point of time and before we were knocking on the front door, they slipped out the back. However, we did get Saddam hung, who was a war criminal for more than two decades. Now if Obama can somehow keep his promise, we will be out of Afghanistan and Iraq, which we left years ago.
While my personal belief that the Iraq War is unwavering even since the war drums were being beaten back in 2002, I don't think the war is necessary based on lies. A lie would infer that there was an intentional part on any person to knowingly pass along information that they believed was untrue. In this case, I think the intelligence was poor and that the Bush Administration used the available knowledge to push their agenda. I think the fault intelligence combined with the American cultural landscape post-9/11 allowed for us to go to war.