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Military Policy & Weapons/Support Troop to Combat Troop Ratios


What is the ratio of support troops to combat infantry currently in the army and marine corps? Please include Iraq and Afghanistan. I read that in Vietnam it was 10 to 1 in the army and 9 to 1 in the USMC. Has this number changed in 40 years? If this is so, how can we expect to win our wars with only 1/10th of the troops actually doing the fighting? by the way, I tried to get into the readiness corps. I was underqualified.


Since World War II; the ratio of U.S. combat troops to combat service support and support has gone from 4 support soldiers to 1 infantryman to 7 support soldiers to 1 infantryman in Iraq and Afghanistan.  These figures generally hold true for both the Army and USMC.

Iraq:  the functional Teeth-to-Tail (T3R) is 1 to 2.5 (combat to noncombat).—40% combat, 36% logistics, 24% HQ/Admin.  Including contractor support, the combat element goes down to 28%. Throughout the 20th century and on into the 21st century, about a third of all soldiers have been organized into operational units.

“As one would expect, the T3R combat proportion declined over time at a relatively steady rate. This trend measures roughly a 2.16 percent decline per each subsequent campaign. There are many possible reasons for this decline. Perhaps the nature of warfare and technology has changed to the extent that lesser combat troops are needed. The large-scale introduction of civilian contractors into expeditionary warfare in the recent Iraq deployment is the most significant of such changes. Increased technology, primarily in the form of digital communications, provides, possibly, higher levels of command and control and situational awareness, allowing for decreased combat forces. Perhaps different types of operations require lower levels of combat troops or more specialized forces. However, as the percentage of combat troops deployed declines, it raises the question of whether such a deployment is, in fact, a military deployment at all, or some other type of operation not requiring military forces, or at least not the general purpose forces traditionally used in most overseas deployments.”
“The Other end of the spear: the tooth-to-tail ratio (T3R) in modern military operations” by John J. McGrath -¬

I highly recommend reading McGrath’s outstanding study on this matter.

Afghanistan:  According to the Congressional Research Service, "As of March 2009, there were 68,197 DoD contractors in Afghanistan, compared to 52,300 uniformed personnel. Contractors made up 57% of DoD's workforce in Afghanistan. This apparently represented the highest recorded percentage of contractors used by DoD in any conflict in the history of the United States."  

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James Bruno


Diplomacy and foreign affairs. How government decision-making takes place. Interactions of the White House, State Dept., Pentagon, Congress and CIA in formulating policy. How governments deal with each other. Area expertise includes Afghanistan, Indochina, Europe, Cuba. Served in Guantanamo. Currently a member of the Diplomatic Readiness Reserve and Standby Response Corps.


23-years as a diplomat with the U.S. State Dept. Previously at the Defense Dept. Prior to joining government, worked as a journalist with major news organizations.

CBS-News, UPI; various newspapers. Bestselling novelist: TRIBE, PERMANENT INTERESTS and CHASM.

M.A. - U.S. Naval War College
M.A. - Columbia Univ.
B.A. - George Washington Univ.

Awards and Honors
Various in government.

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