The United States currently is involved in an extended, low-intensity conflict in Iraq. More precisely, it is involved in a guerrilla war in the Sunni areas of the country, including much of Baghdad proper as well an arc that runs from due west to the north. The almost daily guerrilla attacks against U.S. forces have resulted in nearly 50 deaths since U.S. President George W. Bush declared the end of major military operations; they also have tied down a substantial number of troops in counterinsurgency operations, two of which (Operations Peninsula Freedom and Desert Scorpion) have been launched already. The war is not strategically insignificant, even though the level of intensity is relatively low at this point. Guerrilla warfare can have a disproportionate effect strategically, even when it can be tactically and operationally managed. There are two reasons for this. The first is that it violates the principles of economy of force: The quantity of force required to contain a guerrilla operation is inherently disproportionate because the guerrilla force is dispersed over a large geographic area, and its stealth and mobility requires a much larger force to contain. Second, guerrilla war generates political realities that affect the strategic level of war. Because of the nature of counterinsurgency operations, guerrillas can generate a simultaneous perception of weakness and brutality, regardless of the intentions of the conventional forces. Since guerrillas choose the time and place of their own attacks and use mobility to evade counterattacks, the guerrilla appears to be outfighting the regular forces. Even when they are merely holding their own or even losing, their continued operation generates a sense of power for the guerrillas and weakness for the counterguerrilla force. The nature of counterinsurgency requires that guerrillas be distinguished from the general population. This is extraordinarily difficult, particularly when the troops trying to make the distinction are foreign, untrained in the local language and therefore culturally incapable of making the subtle distinctions needed for surgical identification. The result is the processing of large numbers of noncombatants in the search for a handful of guerrillas. Another result is the massive intrusion of force into a civilian community that may start out as neutral or even friendly, but which over time becomes hostile — not only because of the constant intrusions, but also because of the inevitable mistakes committed by troops who are trying to make sense of what appears to them an incoherent situation. There is another level on which the guerrilla war intersects strategy. The United States invaded Iraq in order to be perceived as a decisive military power and to set the stage for military operations elsewhere. Guerrilla warfare inevitably undermines the regional perception of U.S. power — justly or not — while creating the impression that the United States is limited in what it can do in the region militarily. Thus, the United States is in a tough spot. It cannot withdraw from Iraq and therefore must fight. But it must fight in such a way that avoids four things: 1. It cannot fight a war that alienates the general Iraqi populace sufficiently to generate recruits for the guerrillas and undermine the occupation. 2. It cannot lose control of the countryside; this could destabilize the entire occupation. 3. It cannot allow the guerrilla operation to undermine its ability to project forces elsewhere. 4. It cannot be allowed to extend the length of the conflict to such an extent that the U.S. public determines that the cost is not worth the prize. The longer the war, the clearer the definition of the prize must be. Therefore, the task for U.S. forces is: 1. Identify the enemy. 2. Isolate the enemy from his supplies and from the population. 3. Destroy him. The dos and don'ts of guerrilla warfare are easy to write about, but much more difficult to put into practice. The centerpiece of guerrilla warfare, even more than other types of war, is intelligence. Knowing who the enemy is, where he is and what he plans to do is the key to stopping him. In Vietnam, the North Vietnamese had much better intelligence about these three things than the United States. Over time, despite material weakness, they were able to turn this and a large pool of manpower into victory by forcing the United States to do the four things it should never have done. Since intelligence is the key, we must consider the fact that this war began in an intelligence failure. The core assumption of U.S. intelligence was that once the Baath regime lost Baghdad, it would simply disappear. STRATFOR had speculated that Saddam Hussein had a postwar plan for a national redoubt in the north and northeast, but our analysis rejected the idea of a guerrilla war on the basis that Iraq's terrain would not support one. Nevertheless, it is the strategy the Baathists apparently have chosen to follow. In retrospect, the strange capitulation of Baghdad — where large Iraqi formations simply melted away — appears to have been calculated to some degree. In Afghanistan, the Taliban forces were not defeated in the cities. They declined combat, withdrawing and dispersing, then reorganizing and returning to guerrilla warfare. Hussein appears to have taken a page from that strategy. Certainly, most of his forces did not carry out a strategic retreat to return as guerrilla fighters; most went home. However, a cadre of troops — first encountered as Mujahideen fighters in Basra, An Nasiriyah and Karbala — seem to have withdrawn to fight as guerrillas. What is important is that they have retained cohesion. That does not necessarily mean that they are all being controlled from a central location, although the tempo of operations — daily attacks in different locations — seems to imply an element of planning by someone. It does mean that the basic infrastructure needed to support the operation was in place prior to the war: 1. Weapons and reserve weapons caches placed in locations known to some level of the command. 2. A communications system, whether simply messengers or communications gear, linking components together by some means. 3. Intelligence and counterintelligence capabilities designed to identify targets and limit enemy intelligence from penetrating their capabilities. The central question is how they do this. First, how many and what kind of weapons are stored, and where are they? Not only in terms of conventional weapons, but also of weapons of mass destruction. This is a critical question. We continue to suspect that Hussein had chemical and possibly biological weapons before the U.S.-led war. Where are the weapons now? Are they stored in some way? Are they available for use, for example, against U.S. base camps at some point? Second, what is the command and control system? Are these autonomous units operating without central control, are they centrally controlled or is it a mixed system? Suddenly, the question of Hussein's whereabouts ceases to be irrelevant. Are Hussein and his lieutenants operating the war from a bunker somewhere? How do they communicate with whatever command authority might exist? How can U.S. intelligence penetrate and disrupt the guerrilla movement? The United States is best at electronic and image intelligence. If the guerrillas stay away from electronic communications except in extreme cases, electronic intelligence will not work. As for image intelligence, it might be used to find arms caches, but it is generally not particularly helpful in a guerrilla war at this level. Vo Nguyen Giap, who commanded communist forces against both France and the United States in Vietnam, divided guerrilla war into three stages: 1. Stage one: very small unit, hit-and-run actions without any attempt to hold territory. 2. Stage two: continuation of stage one attacks combined with larger units, regimental and below, engaging in more intense attacks and taking and holding remote terrain as needed. 3. Stage three: conventional warfare against a weakened enemy who is engaged and defeated. Giap argued that the transition between stages is the key to successful guerrilla operations: Too late or too early are the issues. In Iraq, the guerrillas have a separate problem — the terrain makes the concentration of forces too risky. It is one thing to mass several companies of light infantry in the Vietnamese jungle. It is another thing to do the same in the Iraqi desert. The Iraqi Achilles heel is that the transition from the current level of operations is very difficult to achieve. This is the same problem facing the U.S. forces. If a guerrilla war is to be won, the second stage is the point at which it can be won. During the first stage, the ratio between operational costs and damage to the enemy is prohibitive. Carrying out battalion-sized operations to capture or kill three guerrillas is not only exhausting, it also undermines popular support for counterinsurgency measures. In a stage two operation, the ratios are more acceptable. But the Iraqis can't move to stage two without playing into the hands of the Americans. That seems to argue that the Iraqis intend to remain at this level of operations for an extended period of time. How long depends as much on their resources as on their intentions. How many fighters they have, how secure their command system is, where their weapons are located and how many they have will determine the length of the fight. From the U.S. point of view, fighting a retail guerrilla war is the worst possible strategy. The key for the United States is the destruction of the Iraqi guerrilla command and control system. The North Vietnamese had a clearly defined command and control system, but it was in the north and in Cambodia. There were sanctuaries. At this moment, it would appear that the Iraqis have no sanctuary. Therefore, the command centers are within political reach of the United States. The question is where are they? Where are Hussein, his sons and his other commanders? Gen. Abid Hamid Mahmoud al-Tikriti, Hussein's No. 4 commander, was seized today, which certainly represents a breakthrough for the United States. What is not yet clear is whether this is the beginning of the systematic collapse of the guerrilla command structure or whether he was irrelevant to that. Unless the United States is fortunate and this war comprises only a handful of fighters who quickly will be used up, the only strategy the United States has is to find and destroy the command structure. Every army — even a guerrilla army — depends on commanders, communications and supplies. Find and destroy the commanders, and the army will not be able to resist a general offensive. But first you have to find the commanders. Sweeping after foot soldiers will only upset the population; going after the generals is the key. Therefore, the question of where Hussein, his sons and the rest of the officials pictured on the deck of cards is not academic. It has become the heart of the military equation. Erratum: An error was made in stating the number of casualties in this article. While a total of 52 have died since May 1, only 26 of the deaths were combat-related. We regret the error.