Brookings Institute puts together an Iraq Index to measure a variety of critical factors. Pure numbers remain on the of the best ways to report on the war.

I’m using the section “CAUSE OF DEATH FOR US TROOPS” for this analysis.
Total Casualties between March 2003 and May 31st 2007:
Car Bombs: 132(3.8%)
Mortars and Rockets: 113 (3.3%)
RPGs: 81 (2.3%)
Other Hostile Fire: 1,095 (31.5%)
Helicopter Losses: 181 (5.2%)
Non-Hostile Losses: 529 (15.2%)

This is not exact, but the number of dead from non-hostile factors is almost 20%. This is reflective of the low-casualties taken overall.

I graphed the data for 5 variables per month. Red represents the percentage of causalties caused by IEDs. Blue represents Car Bombs/Mortars/RPGs. Green is other hostile fire – primarily small arms.
We can see the main stages of the war. In 2003, the US battled the Iraqi state and the Ba’athist insurgency who used conventional weapons. In 2004, it fought two population-based insurgencies – one Sunni, and the other Shia.

During this time, the number of casualties from RPGs and Mortars fell to nearly 0. This is due to raids that captured these weapons as well as changes in doctrine to minimize casualties. Insurgents redirected car bombs towards civilian targets due to their inefficiency against mobile military targets.

In 2005, the Insurgency turned to relying on IEDs while avoiding direct infantry engagements. IEDs are basically old artillery shells or homemade explosions uses improvised mines and roadside bombs.

The US has created tools and doctrines to minimize casualties. Major highways for transportation were secured early on – which is why we never hear of fuel tankers getting hit. Casualties occur in the Sunni Triangle where Combat units enter unknown territory.

Human intelligence has been increasing since the new COIN strategy went into effect. Tribesmen and civilians are reporting the location of IEDs and handing over info on the insurgent cells. This has been the most valuable source.

Surveillance helps a great deal. The Buckeye aircraft map out locations and can detect changes. There are many other sources of intel but, obviously, no one wants to reveal them because it would diminish their effectiveness.

Doctrine changes minimize casualties. Today, infantry try to talk to their targets. This spreads them out and moves them across unlikely vectors, minimizing the danger of mines.

New technology like the MRAP further reduce technology. Earlier vehicles like the Humvee used flat undercarriages. The MRAP uses a V-shaped sloped armor undercarriage. This deflects the bomb blast away from the soldiers inside. It is replacing the vulnerable Humvees.

Strategy Page calls the IEDs the “Loud Failure.” Basically, mines do not win a war. To win, the insurgents need to overthrow the Iraqi government, expel US forces, gain sufficient popular support, and form their own ruling government. Mines do not really help any of those goals. Historically, mines play a minor defensive role to guard key locations.
The situation runs like this.

Currently, over two thirds of American casualties are caused by these weapons. Getting these bombs made and placed is the single largest expense for the terrorist organizations. But there have been some disturbing trends in the IED department. Three years ago, for each IED used, one American was killed. Now it takes six IEDs to kill one U.S. soldier or marine. The countermeasures to these weapons have been formidable, and this has forced the terrorists to place more and more bombs, at greater expense, and to employ them more effectively.

In addition, planting IEDs makes the insurgent cell vulnerable to detection. More intelligence leads back to bomb makers who are killed or captured. Insurgents rely on less skilled green bomb-makers who produce less effective bombs. They plant even more of these bombs to acheive the same effect, causing wider exposure. This affect is cumulative.

I’ll make two basic statements about IEDs.
1)IEDs will be restricted to Iraq.  It is unlikely they can be used on this scale anywhere else in the world.  The Insurgents require massive amounts of explosives from ammo dumps and this is lacking in theatres outside Iraq.
The Taliban attempted to use IEDs and cheap mines, but they lacked the requisite materials. It is even less likely they can be used in peaceful countries.

2) US technology and doctrine evolved. This will have a long-term effect of reducing mine casualties in Iraq and elsewhere.