Biden has been going to Iraq every six months so he should know if there has been progress or not:

“I’m hoping to … make it clear that the patience of the American people is running very thin,” he added. “Although terrorism is an international problem, Iraqi unity is an Iraqi problem.” Despite these problems however, Biden said progress is being made locally and that the United States military and tribal leaders are making strides against Al Qaeda.
Regarding the presidential campaign, Biden made it clear during his visit today that he is the most informed candidate when it comes to Iraq. When asked why he decided to come to Ramadi, the senator said: “This is my ninth trip. I’ve been here more than the president and more than most of my colleagues. I come about every six months.”