The last US combat brigade has withdrawn from Iraq, bringing combat operations to an end in a war that has lasted more than seven years and claimed the lives of more than 4,000 US troops.The brigade left the country two weeks before an August 31 deadline for the end of Operation.About 50,000 US troops will remain in the country in an advisory capacity, helping to train Iraqi forces in a new mission codenamed Operation New Dawn, which will run until the end of 2011.
