A 'Forever War' in Iraq?

George W. Bush made his famous “mission accomplished” speech on May 1, 2003. But twelve years later, the Iraq mission still doesn’t seem to have quite been accomplished. President Obama announced on Wednesday that he’s sending another 450 US military personnel to Anbar province to “train, advise, and assist Iraqi Security Forces.” In June last year, 275 troops were sent over; in September, another 350; in November, another 1,50. What were the goals of all these deployments, and how close have they come to meeting them?