Did American Soldiers help the Iraqi People to Have More Freedom?

I am writing a persuasive essay on why war is necessary and can benefit our well being as well as the well being of others. One of my pieces of evidence is that we orginally went to Iraq on threats of wmd's but ended up helping the Iraqi people to be more free. I don't really know how we helped them. Keep in mind that my essay has to be 1500 words! Can anyone give advice on how to make a paper this long? Lengthy information would be appreciated. Thanxx!