A while back I wrote on our troop strength in Iraq and concluded we have enough to win. I've calculated we have enough since the fall of 2003 when I did my first rough math.
A DOD press briefing gives me some more numbers to plug in and clarifies something else I speculated about. I had wondered what happened to the facility protection guys that seemed to have dropped off the map. They may not be counted in the official numbers of but they are there and they serve a useful function and should be counted. The same with police not yet trained. If we insist on special forces standards, no Iraqi--friendly or enemy--can be considered "effective." But they can all carry out duties within their abilities.
My updated thoughts are as follows:
American forces are not the only security forces in Iraq. We have (and I'm going partly on memory here so forgive any errors--the general idea will remain valid) 135,000 Americans (after the election surge is withdrawn), 25,000 Coalition, 135,000 Iraqis trained, 35,000 Iraqi police not trained yet, 75,000 facility protection troops, 30,000 Iraqi militia (excluding Kurds), and 20,000 contract security.
This totals 455,000 security personnel.
We should not count this against the full 25 million population since the security forces above exclude Kurds which at one time anyway numbered 70,000. But since Kurdish areas are secure, let's just exclude the Kurdish population and we don't need to count the Kurdish militias.
So we have 455,000 security personnel for 20 million people. This is 2.3%. This itself is enough for security, based on the minimum of 2% (20 troops per 1,000 people) from the historical record. But we have to look at Iraq and not the average. We also have 25,000 personnel in Kuwait supporting the Iraq force. How do we count this? If Kuwait didn't host them, presumably they'd be in Iraq itself. If in Iraq, we'd count them as 25,000 fighting the insurgency. Why should we exclude their value just because they are in a more secure area and not subject to insurgent attacks? Indeed, since they don't need the security of Iraq-based forces, shouldn't we value them higher since they are doing the equivalent job of 25,000 plus security if they were inside Iraq? Let's call them 30,000 assuming a brigade of security would be necessary. I'm being conservative since our 20 brigades in Iraq at 5,000 per brigade works out to 100,000 in combat units and 50,000 non-brigade troops.
Now we are up to 485,000 troop equivalents in Iraq. Now we are up to 2.4%. Even better. But I can smooth some of my original rough edges.
In my past back-of-the-envelope calculations I had divided troops into Kurdish areas (5 million), Shia areas (15 million), and Sunni areas (5 million). Using this method I found sufficient troops although this ethnic breakdown is simplistic since ethnic/religious groups are not distinct in their own geographic areas. Let me assume roughly over half of the Shias and Kurds are in mostly "pure" regions (so I can round to even numbers). So assume that we can really subtract from 25 million total population 3 million Kurds in safe Kurdish areas and 8 million Shias in Shia regions in the south. This leaves us with a population of 14 million in the pacification area of Sunni or Sunni-Shia/Kurd areas to measure our troop strength against.
How are the troops occupying Iraq broken down? I'm going to do more assuming here for the numbers in the pacification area: 135,000 Americans, 20,000-equivalent Americans in Kuwait (I assume some support the Shia areas), 10,000 Contract security (half), 100,000 trained Iraqis (about 3/4 of total), 35,000 facility protection troops (under 1/2 of total), 10,000 Iraqi police not trained yet (less than 1/3 of total), 10,000 Iraqi militia (1/3 of total).
This totals 320,000 in the pacification area leaving 165,000 for the 8-million Shia area. This is almost 2.1%. Well above the light resistance range that characterizes the Shia area and into the numbers that are good enough to fight a serious insurgency. Given the security situation, this is a high presence. At the 0.5% level we'd only need 40,000 security personnel in the Shia area.
Back to the pacification area with Sunni or mixed areas with lots of Sunnis, I'm assuming 8 million people. The 320,000 I've assigned to this area represent 4% of the population. This is well above the historic average of fighting serious insurgencies. And it also gives us a reserve of forces in the Shia areas in excess of its policing requirements and from the Kurdish forces that I don't even count. Perhaps tens of thousands could be moved to the pacification area if needed.
The insurgency keeps going because of all the money that Saddam stole and hid that allows him to pay for bodies, attacks, weapons, and protection in Syria and Iran. But we have the numbers to beat the enemy. If the elections stiffen the resolve of our Iraqi allied soldiers at a faster rate to complement their training and equipping, we will be able to transfer the burden of fighting to the Iraqis faster than we may expect right now.
We don't need more troops. We just need to get Iraqis up to replacing our guys.