Not surprisingly, my surge analysis is deemed too simplistic by a military expert. E-mail:

Dear Rich,
I’ve been a military analyst my entire adult life, which means for close to thirty years now. Let me offer a few observations on some stuff you wrote:
“1) The debate over how many troops are in a brigade seems entirely academic. A brigade is a brigade. It doesn’t matter much how you try to count the number of troops.”
This is too simplistic. A brigade is merely an aggregation of three or four maneuver battalions with some supporting units (artillery, engineers, signals, etc.). There are many kinds of brigades, and if you don’t deploy the right type for the situation, you not only don’t make things better, you can make them worse.
Let’s look at our options here. A light infantry brigade would consist of three dismounted infantry battalions, each of about 750 men, the vast majority of whom would be riflemen. They would be supported by a battalion of towed artillery, a scout company, an engineer company, signals company, medical units and so forth. All told, it would be about 4000 men, of whom about 3000 would actually be infantrymen. This is the ideal kind of brigade to fight an urban insurgency, since the critical ingredient is dismounted infantry able to occupy neighborhoods, close with the enemy, and eliminate him with precision and a minimal amount of collateral damage.
Next would be a Stryker medium brigade, which at present consists of three Stryker battalions totalling about 3500-4500 men and 300-odd Stryker vehicles. Each Stryker has a crew of two and an eight man dismount squad, which means that there are about 2400 dismounted infantry in the brigade. The Strykers give the brigade mobility and some protection, but they aren’t what you want if you’re going to clean out an area and then stick around. They’re better for open areas, or as fire brigades responding to tactical crises.
Then there are heavy brigades, either “armored” or “mechanized”, but essentially consisting of the same types of units–3-4 battalions of tanks and mechanized infantry, the exact mix determined by the operational requirements. A brigade with more tank than mechanized battalions is called “armored”, one with more mechanized battalions is “mechanized”, and one with an equal number is “balanced” (but usually designated “mechanized”). A tank battalion has 58 tanks, each with a crew of four, plus some supporting units (maintenance, logistics, etc.), for a total of 250-300 men. A mechanized battalion has about 60 Bradley Fighting Vehicles, each with a crew of three plus a six man infantry squad (“dismounts”) or about 700 men. A heavy brigade generates awesome amounts of firepower and has considerable armor protection thanks to its vehicles. It can take out a typical enemy armored division and keep going. It can tilt the balance in an urban assault, where the 120mm gun of the tanks and the 30mm cannon of the Bradleys can pulverize buildings and shock enemy troops into retreat or surrender. However, with only six dismounts per Bradley, a mech battalion has only 360 infantrymen, who in fact are trained to fight as part of a combined armed team with their Bradleys and supporting tanks. They aren’t really cut out for fighting in cities, and in fact, ought to avoid it if possible.
So, not only are there vast disparities in the number of men in a brigade, each type of brigade has widely divergent capabilities, and it is the job of the military planner to determine what mix of brigades he needs to fulfill his mission. Unfortunately, the U.S. has far more heavy brigades than it needs, and not nearly enough light brigades for what it needs to do.
“6) At the end of the day, Petreaus wants five brigades and he’s going to get five brigades. A lot of the detailed debate going on about tactics now isn’t particularly relevant, since Petreaus is the one who will ultimately be deciding these questions when he is on the ground in Iraq.”
Undoubtedly, as the author of the Army’s new counter-insurgency doctrine, Petreaus would prefer to have troops trained and equipped for COIN. That means light infantry. But we’re scraping the bottom of the light infantry barrel right now. He’ll probably get one or two brigades of that sort, with the rest consisting of recently rotated Stryker brigades, and perhaps an additional heavy brigade. One advantage of the light brigades is their air transportability–the men and most of their equipment can be flown in either from CONUS or Europe within a couple of weeks. The Stryker brigades are supposed to be “air transportable”, but in fact, their vehicles need considerable disassembly and reassembly before they get on and after they get off the airplane. It’s better to bring them in by sea, which is going to take a month or more. As for any heavy brigades, the men may be able to come in by air, but the equipment has either to come by sea, or from prepositioned stockpiles in Kuwait or Bahrain. Either way, we’re talking about 30-60 days before any heavy brigade is ready to pull its weight.