Although there are only about 9,000 American military personnel in Afghanistan now, versus peak (2011) strength of 98,000, there are still a lot of contractors there. From 2010 through 2013 it was quite different with about 105,000 contractors (on average) in Afghanistan while now there are 26,000. During that period most contractors were foreigners with essential technical skills but at least a quarter were security specialists. Before most American troops left Afghanistan in 2014 there as many as 28,000 (in 2012) foreign security contractors there. Most of these contractors were guarding American bases. With American troops now staying in Afghan run bases, there are only about a thousand foreign security contractors and most of these are guarding the embassy. There was a similar situation in Iraq but the contractor presence was more critical in Afghanistan where the local population did not have the education, skills and experience to replace a lot of Western combat support. Thus while the Afghans and Iraqis now want more American troops to return and help them out the Afghans want more of those contractors. Not just for the essential skills but because they are not military personnel.
By the late 20th century it became customary to use lots of contractors for supply and service tasks, in effect running overseas bases used by American troops and government officials. It was also found practical to also employ contractors to handle some of the base security. These civilians were armed and known as PSC (Private Security Contractors). A lot of them were used in Iraq after 2003 and continued to be used in Afghanistan and Iraq to guard bases, convoys, embassies, and anything or anyone the Islamic terrorists want to attack. In Iraq PSC strength peaked in 2009, with 15,279 PSC personnel. By 2013, after nearly all American troops had left, there were still over 3,000 PSCs there, mostly protecting embassy personnel and foreign aid officials. Another 3,000 such civilian contractors were doing non-combat jobs. At that time the U.S. employed about 18,000 PSC personnel worldwide. The 11,000 or so in Afghanistan not only provide security but also train Afghan police and assist in destroying opium and heroin production. All this PSC activity gets little media coverage and even less interest by reporters regarding the ancient origins of PSCs (and military contractors in general) and how the United States and most other industrialized nations had been using them for centuries.
Instead the media and entertainment industries decided that military contractors were the new bad guys and expended considerable effort inventing and publicizing anything evil about contractors that could be passed off as plausible. This led politicians to demand that many contractor jobs be given back to government employees. This was called "insourcing" and once the implications of this were clearly explained (more expensive, less competent), calls for it to happen quietly disappeared.
The problem, from the beginning, is that the media either didn't understand the use, and history, of military contractors or just ignored that reality. The fact of the matter is that contractors have been around for thousands of years and have become more common against since the 1960s for the simple reason that they are cheaper and more effective than using troops or government employees. Ordering insourcing didn't change that fact of life, as the politicians quickly learned.
The presence of so many civilian contractors in the combat zone was first noted by the mass media in Iraq. There were indeed a lot of contractors there and by 2009 there was one civilian contractor for each member of the military in Iraq. Thus half the American force was civilians. Yet this is not the first time this has happened. In the 1990s, half the American peacekeeping force in the Balkans was civilian contractors. No one noticed it back then. In past wars the percentage varied. During the 1991 Gulf war contractors were only about two percent of the force. That was because the U.S. troops came to liberate Kuwait and leave. Moreover, Saudi Arabia, and other Gulf States, had bases and plenty of civilian workers they allowed U.S. forces to use for the operation. The American troops basically lived "in the field" as they would in a conventional war while local civilians took care of many support tasks.
In the Vietnam War, where U.S. troops were there for a long time, contractors were 16 percent of the force. In the Korean War civilians were 28 percent of the force. During World War II it was 12 percent, it was 4 percent in World War I, during the U.S. Civil War it was 17 percent, during the Mexican-American War it was 15 percent, and during the Revolutionary War it was 18 percent. It was not just the U.S. that was using contractors in Iraq and Afghanistan but many other nations around the world have been doing the same thing. It's particularly popular in Europe, but even Russia and China began picking up on this after the Cold War ended in 1991. And this has been going on everywhere for a long time.
This current trend is actually a return to the past, when many of the "non-combat" troops were civilians. Another major change in modern times is the shrinking proportion of troops who actually fight. A century ago most armies comprised over 80 percent fighters and the rest "camp followers (support troops) in uniform." Today the ratio is reversed and therein resides a major problem. Way back in the day, the support troops were called "camp followers," and they took care of supply, support, medical care, maintenance, and "entertainment" (that's where the term "camp follower" got a bad name). The majority of these people were men and some of them were armed, mainly for defending the camp if the combat troops got beat real bad and needed somewhere to retreat to. The military is using a lot more civilians now. In an age when most troops are highly paid volunteers, it's cheaper to hire additional civilians, on short term contracts, than it is to recruit and train more troops.
The U.S. military has actually been hiring contractors, more and more, since the 1960s, but does not give a lot of publicity to the program. This was mainly because some of the contractors, especially those in medical jobs, get paid far more than someone in uniform doing the same job. But most of the civilians, hired to do what was previously done by soldiers, are making as much, or less, than the troops (including benefits).
Some American generals have suggested dispense with expensive contractors because they believe these people are much more expensive than soldiers would be, doing the same work. That is not always possible, as some of these contractors are technical specialists (as in electronics and communications) for which the military has no counterparts. This has always been the case with medical personnel and with the explosion in new tech in the last half century the need for highly skilled personnel has grown enormously.
The military has always had a lot of civilians around but more of them are now doing jobs in combat zones or out in the field. Many of the PSCs are retired military or have served for a few years. They know the drill and what they are getting into. There is not as much of this in Afghanistan but there is widespread use of armed contractors for convoy escort and base security. You could try to replace some of these because not as many troops are needed in Afghanistan as in Iraq. But this would require more American troops to serve overseas, at a time when the military is trying to give the troops more time at home. Most American active duty and reservist troops have served at least one 12 month tour in Iraq.
One of the great revolutions in military operations in this century has been in the enormous increase in support troops. This came after a sharp drop in the proportion of camp followers in the 18th and 19th centuries. Before that it was common for an army on the march to consist of 10-20 percent soldiers and the rest camp followers. There was a reason for this. Armies "in the field" were camping out and living rough could be unhealthy and arduous if you didn't have a lot of servants along to take care of the camping equipment and help out with the chores. Generals usually had to allow a lot of camp followers in order to get the soldiers, especially the officers and key technical people (who handled artillery and engineering) to go along with the idea of campaigning.
Only the most disciplined armies could do away with all those camp followers and get the troops to do their own housekeeping. The Romans had such an army, with less than half the "troops" being camp followers. But the Romans system was not re-invented until the 18th century, when many European armies trained their troops to do their own chores in the field, just as the Romans had. In the 19th century, steamships and railroads came along and made supplying the troops even less labor intensive and more dependent on civilian support "troops." The widespread introduction of conscription in the 19th century also made it possible to get most of your "camp followers" cheap by drafting them and putting them in uniform.
In the last half century conscription has fallen out of favor, but volunteer troops are too expensive to be used for a lot of support jobs, so more and more of these chores are contracted out to civilians. Even if you're in Iraq or Afghanistan you often won't even notice a lot of the contractor civilians. They often wear army combat uniforms, without any rank insignia. Some are armed. They work for the army without being in the army. But the truth of the situation is that the military has been going back to the past to find the future.
Generals who try to get rid of civilian contractors soon face resistance from subordinate commanders who will point out that more troops assigned to support jobs will mean fewer available for combat. Now the contractors have proved useful to allies as well, especially in the Middle East and Afghanistan, areas where is not enough local talent to support, or sometimes operate, high-tech equipment. .