In short, No. There is absolutely no connection between the two events.
The Holocaust was a state sanctioned event (meaning the government of Germany and other fascist nations organized and sponsored the detainment, torture, and murder of 6 million Jews and 5 million Gypsies, Gays, Communists, Catholics, and political dissidents). The motivation for killing the Jews was purely bigoted. The governments were not motivated by greed (acquiring land, money, or power). Most wars, even those that turn into genocides such as Rwanda, are motivated by greed and power. The Nazis already had power, and the Germans were not a minority class politically or socio-economically. European Anti-Semitism dates back to the Middle Ages and pogroms (Church and government sanctioned attacks on Jews during Holy Week) were commonplace. So attacking Jews was not shocking, surprising, or a stretch for anyone in Europe in 1933-1945.
The Iraq War is a poorly planned war where the US has invaded a foreign country on allegations of violating UN treaties, human rights violations, and involvement in 9/11. Many argue that the US acted out of greed for the oil and for the business it generated for Haliburton. However, the United States government has not been motivated to invade a foreign nation in order to systematically annihilate an entire ethnic group off the planet.
Holocaust Denial is a growing field with a wide spectrum. There are those that deny it ever happened and others who claim it was exaggerated. While others still misuse and abuse the term Holocaust to include all manners of struggle, death, war, and isolation. Doing so diminishes what ALL the poeple who suffered and died during the Holocaust endured. It diminishes what level of institutionalized hatred had to take place in order for an entire continent to be involved. And it puts the world at risk of repeating that horror.
The previous answerer, my friend pohnpei397, suggests that the U.S. went to war in Iraq in order to protect Israel, which was created "largely because of the Holocaust."
It is true that the U.S.A. has been supportive of the State of Israel since its establishment in 1948; it is true that Saddam Hussein was openly hostile to Israel; it is even true that one American motivation for fighting Iraq may have been its desire to protect Israel.
I hope, however, that no one is naive enough to think that the U.S.A.'s primary reason for invading Iraq was in order to protect Israel. There are many other reasons why the U.S.A. chose to fight Iraq. Some of them are:
a) because of tensions dating back to Iraq's invasion of Kuwait and the subsequent Gulf War of 1991;
b) because of the belief (probably mistaken) that Iraq had some connection to the 9/11 attacks;
c) because of the belief (probably mistaken) that Iraq had a stockpile of weapons of mass destruction that it might use itself or share with terrorists;
d) because Iraq is a major oil exporter and the US government wanted to ensure that it be ruled by a stable and West-leaning government.
Holocaust victims and survivors have suffered enough; let's not make them the culprits behind a decision made by a superpower who surely did not consult with them.
I do not believe there is a connection in terms of how people are being treated, if that is what you are asking. In the Holocaust, people were intentionally killed in cold blood because of their ethnicity. In the Iraq War, civilians have been killed, but it has typically been unintentional and the people have been killed because they were in the wrong place at the wrong time (were unlucky), not because they were Muslim.
I suppose you could argue that the Iraq War happened because of the Holocaust (if that is what you are asking). You could argue that the US wants to protect Israel, which it helped create largely because of the Holocaust.
In my opinion the situation in Iraq had very little to do with the Holocaust. Although the United States entered Iraq with the intention to remove Saddam Hussein from his position as dictator, it was not relative to human rights. To this day Americans are left with uncertainty why we went to war there. Americans were told at first it was because the Iraqis had weapons of mass destruction and there was a serious threat that they would use them. Congress then sanctioned the intervention. Many Americans were still angry over 9/11 and equated the issue with 9/11. I just recently read that a poll taken of American citizens beliefs statistically showed that 70% of Americans thought that Saddam Hussein was personally responsible for the 9/11 terrorist acts. However, we know through educational sources that is not true.
Saddam Hussein had proved to be a danger and a risk during the war In Kuwait. He was a threat to America obtaining oil supply as well as other countries. There are many other reasons that American citizens will never know as to why we went into Iraq, but I do not believe it was relative to human rights issues. Therefore, it is not connected to the Holocaust. America had not gone to war with Germany to protect the Jews either.
I don't think that there is any direct cause and effect relationship between Holocaust and Iraq war. However it is always possible to find some vague and long winded relationship between apparently unrelated events also. For example there is a serious scientific theory that states that a minor event like a butterfly fluttering its wings in one part of the world may cause a storm in another. However, it is not possible for human being to know all the cause and effect links, may such events are thought of as random events.
I can think of many possible ways in which holocaust may have influence the Iraq war particularly by way of the role of holocaust in formation of Israel, and influence of Israel on Iraq and US policy towards Iraq. However, it will be difficult to establish any such relationship with confidence and accuracy.