Never Fight a Land War in Asia is republished with permission of STRATFOR.

By George Friedman

U.S. Secretary of Defense Robert Gates, speaking at West Point, said last week that “Any future defense secretary who advises the president to again send a big American land army into Asia or into the Middle East or Africa should have his head examined.” In saying this, Gates was repeating a dictum laid down by Douglas MacArthur after the Korean War, who urged the United States to avoid land wars in Asia. Given that the United States has fought four major land wars in Asia since World War II — Korea, Vietnam, Afghanistan and Iraq — none of which had ideal outcomes, it is useful to ask three questions: First, why is fighting a land war in Asia a bad idea? Second, why does the United States seem compelled to fight these wars? And third, what is the alternative that protects U.S. interests in Asia without large-scale military land wars?

The Hindrances of Overseas Wars

Let’s begin with the first question, the answer to which is rooted in demographics and space. The population of Iraq is currently about 32 million. Afghanistan has a population of less than 30 million. The U.S. military, all told, consists of about 1.5 million active-duty personnel (plus 980,000 in the reserves), of whom more than 550,000 belong to the Army and about 200,000 are part of the Marine Corps. Given this, it is important to note that the United States strains to deploy about 200,000 troops at any one time in Iraq and Afghanistan, and that many of these troops are in support rather than combat roles. The same was true in Vietnam, where the United States was challenged to field a maximum of about 550,000 troops (in a country much more populous than Iraq or Afghanistan) despite conscription and a larger standing army. Indeed, the same problem existed in World War II.

When the United States fights in the Eastern Hemisphere, it fights at great distances, and the greater the distance, the greater the logistical cost. More ships are needed to deliver the same amount of materiel, for example. That absorbs many troops. The logistical cost of fighting at a distance is that it diverts numbers of troops (or requires numbers of civilian personnel) disproportionate to the size of the combat force.

Regardless of the number of troops deployed, the U.S. military is always vastly outnumbered by the populations of the countries to which it is deployed. If parts of these populations resist as light-infantry guerrilla forces or employ terrorist tactics, the enemy rapidly swells to a size that can outnumber U.S. forces, as in Vietnam and Korea. At the same time, the enemy adopts strategies to take advantage of the core weakness of the United States — tactical intelligence. The resistance is fighting at home. It understands the terrain and the culture. The United States is fighting in an alien environment. It is constantly at an intelligence disadvantage. That means that the effectiveness of the native forces is multiplied by excellent intelligence, while the effectiveness of U.S. forces is divided by lack of intelligence.

The United States compensates with technology, from space-based reconnaissance and air power to counter-battery systems and advanced communications. This can make up the deficit but only by massive diversions of manpower from ground-combat operations. Maintaining a helicopter requires dozens of ground-crew personnel. Where the enemy operates with minimal technology multiplied by intelligence, the United States compensates for lack of intelligence with massive technology that further reduces available combat personnel. Between logistics and technological force multipliers, the U.S. “point of the spear” shrinks. If you add the need to train, relieve, rest and recuperate the ground-combat forces, you are left with a small percentage available to fight.

The paradox of this is that American forces will win the engagements but may still lose the war. Having identified the enemy, the United States can overwhelm it with firepower. The problem the United States has is finding the enemy and distinguishing it from the general population. As a result, the United States is well-suited for the initial phases of combat, when the task is to defeat a conventional force. But after the conventional force has been defeated, the resistance can switch to methods difficult for American intelligence to deal with. The enemy can then control the tempo of operations by declining combat where it is at a disadvantage and initiating combat when it chooses.

The example of the capitulation of Germany and Japan in World War II is frequently cited as a model of U.S. forces defeating and pacifying an opposing nation. But the Germans were not defeated primarily by U.S. ground troops. The back of the Wehrmacht was broken by the Soviets on their own soil with the logistical advantages of short supply lines. And, of course, Britain and numerous other countries were involved. It is doubtful that the Germans would have capitulated to the Americans alone. The force the United States deployed was insufficient to defeat Germany. The Germans had no appetite for continuing a resistance against the Russians and saw surrendering to the Americans and British as sanctuary from the Russians. They weren’t going to resist them. As for Japan, it was not ground forces but air power, submarine warfare and atomic bombs that finished them — and the emperor’s willingness to order a surrender. It was not land power that prevented resistance but air and sea power, plus a political compromise by MacArthur in retaining and using the emperor. Had the Japanese emperor been removed, I suspect that the occupation of Japan would have been much more costly. Neither Germany nor Japan are examples in which U.S. land forces compelled capitulation and suppressed resistance.

The problem the United States has in the Eastern Hemisphere is that the size of the force needed to occupy a country initially is much smaller than the force needed to pacify the country. The force available for pacification is much smaller than needed because the force the United States can deploy demographically without committing to total war is simply too small to do the job — and the size needed to do the job is unknown.

U.S. Global Interests

The deeper problem is this: The United States has global interests. While the Soviet Union was the primary focus of the United States during the Cold War, no power threatens to dominate Eurasia now, and therefore no threat justifies the singular focus of the United States. In time of war in Iraq and Afghanistan, the United States must still retain a strategic reserve for other unanticipated contingencies. This further reduces the available force for combat.

Some people argue that the United States is insufficiently ruthless in prosecuting war, as if it would be more successful without political restraints at home. The Soviets and the Nazis, neither noted for gentleness, were unable to destroy the partisans behind German lines or the Yugoslav resistance, in spite of brutal tactics. The guerrilla has built-in advantages in warfare for which brutality cannot compensate.

Given all this, the question is why the United States has gotten involved in wars in Eurasia four times since World War II. In each case it is obvious: for political reasons. In Korea and Vietnam, it was to demonstrate to doubting allies that the United States had the will to resist the Soviets. In Afghanistan, it was to uproot al Qaeda. In Iraq, the reasons are murkier, more complex and less convincing, but the United States ultimately went in, in my opinion, to convince the Islamic world of American will.

The United States has tried to shape events in the Eastern Hemisphere by the direct application of land power. In Korea and Vietnam, it was trying to demonstrate resolve against Soviet and Chinese power. In Afghanistan and Iraq, it was trying to shape the politics of the Muslim world. The goal was understandable but the amount of ground force available was not. In Korea, it resulted in stalemate; in Vietnam, defeat. We await the outcome in Iraq and Afghanistan, but given Gates’ statement, the situation for the United States is not necessarily hopeful.

In each case, the military was given an ambiguous mission. This was because a clear outcome — defeating the enemy — was unattainable. At the same time, there were political interests in each. Having engaged, simply leaving did not seem an option. Therefore, Korea turned into an extended presence in a near-combat posture, Vietnam ended in defeat for the American side, and Iraq and Afghanistan have turned, for the time being, into an uncertain muddle that no reasonable person expects to end with the declared goals of a freed and democratic pair of countries.

Problems of Strategy

There are two problems with American strategy. The first is using the appropriate force for the political mission. This is not a question so much of the force as it is of the mission. The use of military force requires clarity of purpose; otherwise, a coherent strategy cannot emerge. Moreover, it requires an offensive mission. Defensive missions (such as Vietnam and Korea) by definition have no terminal point or any criteria for victory. Given the limited availability of ground combat forces, defensive missions allow the enemy’s level of effort to determine the size of the force inserted, and if the force is insufficient to achieve the mission, the result is indefinite deployment of scarce forces.

Then there are missions with clear goals initially but without an understanding of how to deal with Act II. Iraq suffered from an offensive intention ill suited to the enemy’s response. Having destroyed the conventional forces of Iraq, the United States was unprepared for the Iraqi response, which was guerrilla resistance on a wide scale. The same was true in Afghanistan. Counterinsurgency is occupation warfare. It is the need to render a population — rather than an army — unwilling and incapable of resisting. It requires vast resources and large numbers of troops that outstrip the interest. Low-cost counter-insurgency with insufficient forces will always fail. Since the United States uses limited forces because it has to, counterinsurgency is the most dangerous kind of war for the United States. The idea has always been that the people prefer the U.S. occupation to the threats posed by their fellow countrymen and that the United States can protect those who genuinely do prefer the former. That may be the idea, but there is never enough U.S. force available.

Another model for dealing with the problem of shaping political realities can be seen in the Iran-Iraq war. In that war, the United States allowed the mutual distrust of the two countries to eliminate the threats posed by both. When the Iraqis responded by invading Kuwait, the United States responded with a massive counter with very limited ends — the reconquest of Kuwait and the withdrawal of forces. It was a land war in Asia designed to defeat a known and finite enemy army without any attempt at occupation.

The problem with all four wars is that they were not wars in a conventional sense and did not use the military as militaries are supposed to be used. The purpose of a military is to defeat enemy conventional forces. As an army of occupation against a hostile population, military forces are relatively weak. The problem for the United States is that such an army must occupy a country for a long time, and the U.S. military simply lacks the ground forces needed to occupy countries and still be available to deal with other threats.

By having an unclear mission, you have an uncertain terminal point. When does it end? You then wind up with a political problem internationally — having engaged in the war, you have allies inside and outside of the country that have fought with you and taken risks with you. Withdrawal leaves them exposed, and potential allies will be cautious in joining with you in another war. The political costs spiral and the decision to disengage is postponed. The United States winds up in the worst of all worlds. It terminates not on its own but when its position becomes untenable, as in Vietnam. This pyramids the political costs dramatically.

Wars need to be fought with ends that can be achieved by the forces available. Donald Rumsfeld once said, “You go to war with the Army you have. They’re not the Army you might want or wish to have at a later time.” I think that is a fundamental misunderstanding of war. You do not engage in war if the army you have is insufficient. When you understand the foundations of American military capability and its limits in Eurasia, Gates’ view on war in the Eastern Hemisphere is far more sound than Rumsfeld’s.

The Diplomatic Alternative

The alternative is diplomacy, not understood as an alternative to war but as another tool in statecraft alongside war. Diplomacy can find the common ground between nations. It can also be used to identify the hostility of nations and use that hostility to insulate the United States by diverting the attention of other nations from challenging the United States. That is what happened during the Iran-Iraq war. It wasn’t pretty, but neither was the alternative.

Diplomacy for the United States is about maintaining the balance of power and using and diverting conflict to manage the international system. Force is the last resort, and when it is used, it must be devastating. The argument I have made, and which I think Gates is asserting, is that at a distance, the United States cannot be devastating in wars dependent on land power. That is the weakest aspect of American international power and the one the United States has resorted to all too often since World War II, with unacceptable results. Using U.S. land power as part of a combined arms strategy is occasionally effective in defeating conventional forces, as it was with North Korea (and not China) but is inadequate to the demands of occupation warfare. It makes too few troops available for success, and it does not know how many troops might be needed.

This is not a policy failure of any particular U.S. president. George W. Bush and Barack Obama have encountered precisely the same problem, which is that the forces that have existed in Eurasia, from the Chinese People’s Liberation Army in Korea to the Taliban in Afghanistan, have either been too numerous or too agile (or both) for U.S. ground forces to deal with. In any war, the primary goal is not to be defeated. An elective war in which the criteria for success are unclear and for which the amount of land force is insufficient must be avoided. That is Gates’ message. It is the same one MacArthur delivered, and the one Dwight Eisenhower exercised when he refused to intervene in Vietnam on France’s behalf. As with the Monroe Doctrine, it should be elevated to a principle of U.S. foreign policy, not because it is a moral principle but because it is a very practical one.