Coalition forces in Iraq have suddenly received the manpower equivalent of three light infantry divisions. They did not suffer any repercussions in domestic politics as a result, and now have a huge edge over al-Qaeda in al-Anbar province. How did this happen? Tribal leaders in the largely Sunni province on the Syrian border got together and signed an agreement to raise a tribal force of 30,000 fighters to take on foreign fighters and terrorists.

These leaders have thrown in with the central government in Baghdad. This is a decisive blow to al Qaeda, which has been desperately trying to fight off an Iraqi government that is getting stronger by the week. Not only are the 30,000 fighters going to provide more manpower, but these tribal fighters know the province much better than American troops – or the foreign fighters fighting for al Qaeda. Also, this represents just over 80 percent of the tribes in al-Anbar province now backing the government.

The biggest gain for the coalition is that they will now have forces on their side that know the terrain in al Anbar province. This is a very big deal in a campaign against the terrorists. When a force knows the terrain, it can make life miserable for its enemies. Just ask any Army unit that has gone through the National Training Center at Fort Irwin. The OPFOR (Opposing Force) has fought there for so long that they know all the good ambush sites. Units coming there for a training session don't have that knowledge – and they pay the price in the exercises held there.

This is just one sign that the tide is turning in favor of the coalition in Iraq. Many of the Sunni leaders have decided that the Shia-dominated Iraqi government is not going away any time soon, nor is the democratic process. As such, the tribal leaders have now decided that it is better to be on their good side rather than to be seen as uncooperative. Constant Arab casualties in al Qaeda attacks – and al Qaeda's desire for a caliphate – have not helped matters any, either.

On the other hand, by signing up with the government, these tribal leaders will hasten the construction of government services, and gain something else just as valuable – the government's gratitude. In essence, the tribal leaders have slowly been won over by a combination of coalition perseverance and al Qaeda strategic ineptness.

This agreement, if it holds, is a win for the United States, which is looking for measurable progress. It is a win for the Shia-dominated Iraqi government, which will now have an easier time in that province. It is a win for the tribal leaders, who will get a few markers they can call in down the road from the government for their assistance. For al Qaeda, now facing the equivalent of three additional light infantry divisions composed of people who will have knowledge of al Anbar province, it is a huge loss. The major downside is that many of the tribesmen still support al Qaeda, and will defy their tribal leaders by continuing to work with the terrorists, or by not being very enthusiastic in fighting the terrorists.