CHAPTER 1

Introduction

Tactical doctrine stresses that urban combat operations are conducted only when required and that built-up areas are isolated and bypassed rather than risking a costly, time-consuming operation in this difficult environment. Adherence to these precepts, though valid, is becoming increasingly difficult as urban sprawl changes the face of the battlefield. The acronym MOUT (Military Operations on Urbanized Terrain) classifies those military actions planned and conducted on a terrain complex where manmade construction impacts on the tactical options available to commanders. Commanders must treat the elements of urban sprawl as terrain and know how this terrain affects the capabilities of their units and weapons. They must understand the advantages and disadvantages urbanization offers and its effects on tactical operations.

Urban combat operations may be conducted in order to capitalize on the strategic or tactical advantages which possession or control of a particular urban area gives or to deny these advantages to the enemy. Major urban areas represent the power and wealth of a particular country in the form of industrial bases, transportation complexes, economic institutions, and political and cultural centers. The denial or capture of these centers may yield decisive psychological advantages that frequently determine the success or failure of the larger conflict. Villages and small towns will often be caught up in the battle because of their proximity to major avenues of approach or because they are astride lines of communications that are vital to sustaining ground combat operations.

During offensive operations, commanders must seek to achieve a favorable mobility differential over the defender, to retain momentum, and to avoid a protracted and costly urban battle. Built-up areas are obstacles to maneuver; hence, isolation and bypass, which neutralize their value to the defender, are the goals of urban offensive operations.

Conversely, the defender must seek to integrate the elements of urban sprawl into his defensive scheme to slow, block, or canalize the attacker and enhance weapon effectiveness.

The attack or defense of a built-up area should be undertaken only when significant tactical or strategic advantage accrues through its seizure or control.

Urbanization is a complex, multifaceted process influenced by many factors including a nation's cultural development, its economic resources, and its industrial capacity. Although its form varies from region to region, urbanization is characterized by a general pattern of changes in land usage and the spread of manmade features across natural terrain.

Tactical terrain analysis has traditionally considered some elements of the urban environment such as the allocation of land to agriculture or forestry and the distribution of railway or road networks. However, the focus has been on natural terrain elements. In Europe and other urbanized areas of the world, increased awareness of the effects of manmade features on the overall tactical scheme is necessary. How urban terrain elements impact on operations is an important consideration in determining our tactical options.

For the small-unit tactical commander, the physical layout of a buildup area and structural characteristics of its buildings are critical planning considerations. Appendix A provides a detailed discussion of these factors and the combat characteristics of various types of built-up areas for offensive and defensive operations. For commanders at battalion level and above, the size of a built-up area, the support network of lines of communication, and the urban pattern formed by a complex of built-up areas assume added importance.

BUILT-UP AREAS

The following discussion uses the central European setting to describe these aspects of urbanization. With minor modifications, it is applicable to other urban areas throughout the world.

A built-up area is a concentration of structures, facilities, and population which form the economic and cultural focus for the surrounding area. There are four categories:

Large Cities
(Population Greater than 100,000.)

Most typical of the urbanization process is the increasing number of large and still-growing large cities. In Europe, other than the Union of Soviet Socialist Republics (USSR), there are approximately 375 cities with populations in excess of 100,000. The Federal Republic of Germany (FRG) has 49 cities with populations exceeding 100,000 and 4 cities of over 1 million. Large cities frequently form the core of a larger, densely populated urban complex consisting of the city, its suburban areas, and small towns. Such complexes have the appearance of a single, large, and continuous city containing millions of people and occupying vast areas of land. The illustration on the following page depicts major complexes that exist in FRG. The Rhine-Ruhr complex stretches west to Aachen and south to Bonn and contains over 12.5 million people concentrated in 13,000 square kilometers. The Rhine-Main complex includes Frankfurt Darmstadt, Mainz, Mannheim, and Karlsruhe; it contains over 5 million people in 7,000 square kilometers. To the southeast, greater Stuttgart (2 million people in 3,000 square kilometers) will soon merge with Rhine-Main. These urban centers encompass 10 percent of FRG's total land area and approximately one-half of its total population.

Towns and Small Cities
(3,000 - 100,000.)

Within the FRG there are approximately 235 small cities/towns with populations from 3,000 - 100,000. In many cases these areas are located along major lines of communications and situated in river valleys. Similar to larger cities, these areas are continuing to expand and will eventually form new conurbations or merge with existing ones.

Villages.
(Less than 3,000.)

In the FRG there are approximately 21,000 built-up areas with populations of less than 3,000. In most cases these villages are agriculturally oriented and are usually distributed among the more open cultivated areas of Germany. In the average brigade sector in the FRG there are 25 of these villages. The average distance between them is only 3.5 kilometers.

Strip Areas

These built-up areas generally form connecting links between villages and towns. They are also found along lines of communications leading to larger complexes. Although the size and population of strip areas vary, they normally assume a long thin linear pattern.

Figure 1-3. Major Urban Complexes.

BUILDING AND STREET PATTERNS

The physical layout of built-up areas is of tactical significance. Five basic building and street patterns which impact on fire support and maneuver schemes recur throughout western Europe. Appendix A provides a detailed analysis of the tactical implications of each pattern. For ease of reference, they have been identified by form and assigned a letter designation. The following table briefly summarizes the general characteristics of each pattern.

        TYPE                             GENERAL CHARACTERISTICS

A. Dense, Random Construction Typical old inner city construction with narrow winding streets radiating in an irregular manner from a central area. Found within cities, towns, and villages. Buildings are located close together and frequently along the edge of roadways.

B. Closed-orderly Block Common to central areas of towns and cities. Wider streets forming generally rectangular patterns with buildings frequently forming a continuous front along a block. Inner block courtyards are common.

C. Dispersed Residential Area Normally contiguous to Type B areas. Consists of rowhouses or single dwellings with yards, gardens, trees, and fences. Street pattern is normally rectangular or curving.

D. High-rise Area Typical of modern construction in larger towns or cities. Consists of multi apartments, separated large open areas and one-story buildings. Wide streets are laid out in rectangular patterns.

E. Industrial/Transportation Older complexes may be found within Type A and B areas. New construct -normally consists of low, flat-roofed factory and warehouse buildings. Generally located on or along the major rail and highway routes of the urban complex.

LINES OF COMMUNICATION (LOC)

A vast network of modern highways, all-weather roads, railroads, and canals connect the FRG's built-up areas. These LOCs permit rapid access to virtually all areas in western Europe. Areas formerly considered to be terrain-restrictive for movement can now be rapidly traversed. Modern four-lane highways, capable of accommodating thousands of heavy vehicles, crisscross NATO-Europe. Frequently, these highways bypass the larger cities, or at least avoid the congested centers of most built-up areas. There is a limitation, however, inherent in these lines of communication. They are often built across terrain that is relatively impracticable for vehicular traffic movement, and are heavily dependent on a system of bridges, ramps, and overpasses. If these systems can be destroyed, the LOCs may then become virtually useless and an obstacle in themselves.

URBAN PATTERNS

The combination of built-up areas, lines of communication, and natural terrain results in the formation of basic urban patterns that impact on tactical operations.

Hub Phenomenon

Central to any urban pattern is the hub or built-up area. Although it may vary in size from village to major urban complex, the effects of a hub remain constant. For the defender, the hub may serve as the pivot or anchor of his defense or as an element of a defense in depth. As shown, the hub is an obstacle which blocks the attacker's advance. Where adjacent natural terrain permits, a hub will normally be bypassed.

Figure 1-6. Hub Phenomenon.

This requires a change in direction of advance and may reduce offensive momentum and cohesion. As the attacker slides off the leading edge of the hub and begins his bypass operation, his vulnerability to flank attacks and ambushes along the new axis of advance increases.

Where adjacent natural terrain is unsuitable for mounted operations, the hub may be developed as a defensive strongpoint. The decision to attack will require significant forces and could result in time consuming, intensive close combat in the built-up area.

Satellite Pattern

This is a common pattern with its central hub and relatively dependent, dispersed, smaller built-up areas. It is typical of the village-town-small city pattern found within a brigade or perhaps division sector. Lines of communication tend to focus on the central hub, with most taking the form of farm and forest or secondary roads. Seldom will more than one major communications route pass through the central hub of the satellite pattern. The natural terrain and cultivated portions throughout the area are relatively homogeneous. Operations on urbanized terrain find built-in mutual support in this pattern. Outlying or satellite urban centers support the principal urban area at the hub by providing:

Figure 1-7. Satellite Pattern.

Network Pattern

Similar in initial appearance to the satellite pattern, the network is vastly more complex and diverse. It represents the interlocking of the primary hubs of subordinate satellite patterns and most often occurs at division or higher levels. Formed primarily of towns and cities, its elements are more self-sufficient and less supportive of each other, although a dominant hub may exist. Major lines of communication within a network are more extensive than in a satellite pattern and take a rectangular rather than convergent form. The natural terrain within a network may be more varied than that contained in a single satellite array.

The tactical effects on offensive operations are: to cause delay, in that attacking units must fight their way through a maze of manmade features that provide defensive obstacles; and, to make bypass difficult because natural contiguous terrain frequently is impracticable for mounted operations (e.g., steep slopes, rivers, and heavily forested areas). This pattern provides depth to the defense.

Figure 1-8. Network Pattern

Linear Pattern

A subelement of the basic geometric patterns, the linear array may form one ray of the satellite pattern or be found along connecting links between the hubs of a network. Most frequently, the linear array results from the stringing of minor hubs along a confined natural terrain corridor such as an-elongated valley approach. It may also occur along the banks of a water course or manmade communications route. To the defender, this pattern facilitates the development of a series of strong defensive positions in depth. To the attacker, it presents a series of decision points, delaying his canalized forces and requiring repetitive deliberate attacks. This pattern is frequently found within a battalion zone of responsibility, although it may extend in width and depth throughout a brigade area.

Segment or Pie Slice Pattern

This pattern may occur as a subset of either the satellite of network patterns or within a major hub. It is characterized by the splitting of an urban area by dominant natural terrain such as a river or by manmade features such as roads, railways, and canals. When such a division of other patterns occurs, it may influence the assignment of boundaries and other control measures or attack objectives. It may also bear directly on the organization of the terrain and task organizations. This pattern may be detected on urban terrain at any level of command.

PATTERN EFFECTS

In addition to the basic blocking action which may be caused by the hub phenomenon, other effects can be associated with these patterns.

The Funnel-Fan Effect

This effect normally occurs at battalion or brigade level when a hub is located between terrain features that are unsuitable for mounted operations. Passage of units into the area results in the concentration of forces, a loss of momentum, and canalization. Beyond the hub, forces are required to spread or fan out before full combat power can again be developed. In each case this effect favors defense and hinders offense. It causes an accordion action in units moving through the hub, with increased difficulties in command and control and reduced operating effectiveness. A similar effect on maneuver takes place when the attacker must penetrate an urban network on a narrow front between hubs.

The Funnel Effect

Funnelling or concentration and canalization of forces may occur without the immediate fanning. Again, this effect most frequently occurs at battalion or brigade level when a linear pattern is encountered. It favors the defender by limiting the number of maneuver elements that may be applied against a series of hubs that must be confronted in succession. Greater reliance must be placed by the attacker on indirect and long-range weapon systems. At the same time, it reduces maneuver options available to the defender and routes available for his combat service support elements.

Figure 1-9a . Segment or Pie Slice Pattern

Figure 1-9b Funnel-Fan Effects

TACTICAL IMPLICATIONS

Urbanization is gradually changing the face of the battlefield. Traditional avenues of approach are being blocked and narrowed by manmade features. Urban areas are growing along lines of communications and expanding across the adjacent terrain. This trend is resulting in the concentration of built-up areas and road networks along natural corridors bounded by forests, slopes, marshes, and bodies of water.

The following example illustrates an effect of this process on military operations on urbanized terrain:

The Meiningen Corridor is a broad, high-speed approach permitting armor forces some freedom to maneuver. Throughout the corridor, however, there are a number of villages and towns flanked by restrictive terrain. To the defender, this corridor offers an in-depth system of instant battle positions in the succession of villages spaced from 2 to 4 kilometers apart. Mutual support can be achieved throughout this corridor by integrating village battle positions with adjacent natural terrain obstacles and positions.

To an attacker, the corridor's urban features represent a series of manmade obstacles. Advancing forces that attempt to bypass individual villages and towns are susceptible to flank attacks. The attacker may be required to conduct frequent combined arms attacks which greatly reduce offensive momentum and increase battle losses.

CHARACTERISTICS OF URBAN WARFARE

Some general characteristics of military operations on urbanized terrain apply to both offensive and defensive. operations. Although they are discussed in subsequent chapters, they are presented here in capsule form because of their importance to an understanding of urban warfare.

The decision to attack or defend an urban complex can result in massive damage and destruction. Constraints on firepower to insure minimum collateral damage within its built-up areas can be expected. Combat operations may be hampered by the presence of civilians in the battle area. Concern for their safety can seriously restrict the combat options open to the commander. The necessity to provide life support and other essential services to civilians can siphon off a substantial amount of military resources and manpower. A hostile population may also impose a serious security problem. Success may well be measured by how we accomplish our mission while minimizing destruction of buildings and alienation of the population. On the urban battlefield, advantages and disadvantages in the areas of mobility, cover, and observation tend to even out for attacker and defender. Initially, however, the defender has a significant tactical advantage over the attacker because of his knowledge of the terrain.

Unlike deserts, forests, and jungles which confront the commander with a limited variety of fairly uniform, recurring terrain features, the urban battlefield is composed of an ever-changing mix of natural and manmade features. Frequently, commanders of larger forces will have units fighting on open terrain, on terrain within built-up areas, and on a complex where these two distinct terrain forms merge.

Urban sprawl expands the scope of the commander's terrain analysis and influences the organization and positioning of forces, weapons employment, and maneuver. The dominant role of armor and mechanized infantry on open terrain is balanced by the requirement to fight in that portion of the urban environment which favors the employment of infantry supported by other arms. Manmade features dispersed in varying densities provide increased cover and concealment while frequently restricting observation and fields of fire. These features are also obstacles to maneuver and are to be avoided by an attacker and used by the defender.

Urbanized terrain normally offers numerous avenues of approach for mounted maneuver well forward of and leading to urban areas. In the proximity of its built-up areas, however, such routes generally become convergent and restrictive. Bypass may be blocked by urban sprawl and the nature of adjacent natural terrain. Avenues of approach within built-up areas are determined by street patterns, building arrangements, open areas, and underground systems. Mounted forces are restricted to streets, alleys, and open areas between buildings. Dismounted forces maximize available cover by moving through buildings and underground systems, along edges of streets, and over roofs.

Fighting within a built-up area is characterized by a three-dimensional battle. In addition to fighting the enemy at street level, fighting may also be conducted on roofs and in the upper stories of buildings and below street level in sewer systems, subways, and other underground structures. Assets and resources may be required to deny, retain, secure, or monitor each dimension. It cannot be assumed that the enemy is not there.

Weapons employment and target-acquisition ranges are greatly reduced by urban features. On the approaches to urban areas, visibility frequently extends to less than 1200 meters. Within built-up areas, targets will generally be exposed for brief periods, frequently at ranges of less than 100 meters. These limitations induce close, violent combat between opposing forces, placing great reliance on automatic weapons, rocket launchers, handgrenades, and hand-emplaced high explosives.

Urban features also increase the difficulty of maintaining effective communications. Tactical radios, the backbone of command and control networks, will be extremely range-limited within built-up areas.

Operating from, within, or through urban areas isolates and separates units. Frequently, operations are reduced to a series of small-unit battles. Greater dependence is placed on the individual soldier's and small-unit leader's initiative, skill, and fortitude.

In possibly no other form of combat are the pressures of battle more intense. Continuous close combat, high casualties, the fleeting nature of targets, and fires from a frequently unseen enemy produce severe psychological strain and physical fatigue particularly among small-unit leaders and soldiers.

In combination, the general characteristics of urban warfare make it more difficult to apply basic tactical fundamentals and maintain control. Military operations on urbanized terrain require detailed planning that provides for decentralized execution.

SUMMARY

Urbanization impacts on military operations by adding the element of urban sprawl to the existing terrain complex. It does not change basic tactical doctrine, but requires that commanders understand how these elements may affect the capabilities of their units and weapons.

Built-up areas must be treated as terrain factors during the planning for and conduct of all military operations on urbanized terrain. Those providing tactical or strategic advantages to a defender will be integrated into his overall defensive scheme. Regardless of their size or configuration, built-up areas are obstacles to maneuver along the lines of communication or route of advance for at least one portion of an attacking force. Their value as an obstacle should be neutralized by isolation and bypass whenever feasible. Built-up areas should be attacked only when no other alternative is available.