Troops of the 37th Infantry Division carried weapons in Manila until 17 March.  Since the end of the fighting on 3 March, things had been done on a more relaxed basis.  New movies were brought to the units every other night.  Seats for the troops were placed in open air, and the block of seats then roped off because of the crowds of civilians who also came and watched.  Most of the units began holding dances weekly, attended by Filipinas and expatriate women.  The Division Special Service Band sometimes played for these events, though the 2d  Battalion of 129th Infantry Regiment had its own orchestra.  Troops had fresh food every day, and there were no epidemics.  Unit staffs also caught up on paperwork, replenished supplies, and began training the hundreds of arriving replacements.  This respite was short-lived, however.  37th Infantry Division marched out of Manila on 29 March to begin its next campaign. [xlvi]

The Japanese defense of Manila had failed.  Nevertheless, there are some remarkable features of the Japanese effort.  On the one hand, Japanese operations show the shortcomings of trying to fight without training, doctrine, or equipment, and without significant joint support.  On the other hand, the Japanese showed how much could be done in defense of a city with nothing to work with but resolute personnel and the resources of a great metropolis. 

Japanese tactics were simple but effective.  Troops fought in small units that tenaciously defended particular assigned positions.  They conducted a static defense with almost no maneuver or coordinated action between positions.  On the streets north of the Pasig they set up minefields and obstacles covered by interlocking machine gun fires.  The mines were often made of artillery shells, depth charges, or aerial bombs, and the machine guns were often dismounted naval aviation machine guns.    In strongpoints south of the Pasig, the Japanese set up positions in sturdy reinforced-concrete buildings and sometimes put foxholes outside.  Typically they swept the approaches with automatic fires sighted through windows or loopholes.  They put sandbagged machine gun nests throughout these buildings, sometimes fortified cellars and roofs, and sometimes fired through holes cut in walls, ceilings and floors.  In most cases, they chose neither to surrender nor retreat, but instead died in place. 

U.S. infantry who faced these positions perceived them as formidable.  Nonetheless, it is remarkable what these positions lacked.  They had little artillery, no armor, no air support, and few suppressive fire weapons for the close fight.  They had almost no field radios allowing communication between units, and almost no trenches or tunnels connecting units.  They had almost no underground positions except cellars in buildings.  There were limited numbers of Japanese to man these positions: Iwabuchi had only 5,000 troops in the central Manila force.  There was also limited time to prepare: the Japanese army had decided to leave Manila in December 1944.

The Japanese had few artillery pieces compared to the Americans, most of them converted naval guns.  They fired isolated rounds randomly or against preregistered  junctions or bridges.  Apparently, they had no forward observers with radios to direct fires, and perhaps also had comparatively limited ammunition.  The Japanese appeared to be short on close-range suppressive fire weapons also.  There is no report of their using flamethrowers or submachine guns.  They had grenades, but sometimes used Molotov cocktails, suggesting local shortages.  Most but not all had rifles.  Some of the rifles were U.S. makes captured in 1942.  In place of rifles, some carried jury-rigged spears made of bayonets on poles.  In other words, the Japanese were woefully lacking in both heavy weapons and light weapons.  All they really had in abundance were machine guns and automatic cannon.  They were fighting the Battle of Manila with naval aviation equipment, not ground warfare equipment. [xlvii]

The Japanese naval defenders in Manila had military discipline and dedication.  But they had no doctrine, no training, no armor, no air, little artillery, no communication between positions, no maneuver, no coordination and no reinforcements.  Nonetheless, they held the Americans at bay for four weeks.  They showed what could be done by defenders who had nothing to work with but their own resoluteness, urban terrain, and the abundant resources of a great city.  The Battle of Manila shows that urban warfare significantly favors the defender. 

Although the Japanese navy conducted a remarkable ad hoc defense in Manila, U.S. forces ground their way steadily through the Japanese positions.  American tactics were decisively more effective.  What were the Americans doing that allowed them to advance?  U.S. forces in Manila were practicing modern combined arms warfare against a static defense.  They were trained ground forces with abundant troops, equipment, and service assets.  They were experienced in fighting in restrictive jungle terrain.  To their credit, they used all the assets available to them, except for some capabilities of airpower. 

Corps and division staffs made sure that regiments and battalions were operationally and tactically coordinated.  Tanks were used to the maximum for direct fires and suppressive fires from the time they became available to 37th Infantry Division on 14 February, and by 1st Cavalry Division throughout.  Airpower, however, was never used to bomb or strafe Japanese positions in the city of Manila, as MacArthur repeatedly denied requests from subordinate units for air bombardment.  This was a major departure from U.S. combined arms doctrine, justified by MacArthur’s desire to spare Philippine civilians in the city.  Airpower was used in other ways, however.  Cub planes were used continuously for artillery spotting.  The 1st Cavalry Division used airpower, indeed joint airpower, for close air support and scouting in the division’s sweep around the outer edge of the city.  Marine Air Groups 24 and 32, flying from an airstrip near Lingayen Gulf, kept nine SBDs over 1st Cavalry Division’s leading elements, and P-40s from the 5th Air Force flew reconnaissance missions to 1st Cavalry’s left and front.  Moreover, U.S. airpower closed the skies completely to Japanese aircraft. [xlviii]

The restrictions on air bombardment within the city may have mattered little, however, because the enemy was contained within a confined space easily within artillery range.  U.S. forces had abundant artillery assets and could get effects similar to those of air bombardment by employing massed artillery.  Initially, artillery fires were also limited by MacArthur to “observed fire on known targets.”  These restrictions were abandoned on 10 February because of mounting U.S. casualties.  This was shortly after the 37th Infantry Division had crossed the Pasig and encountered developed Japanese strongpoints.  Permission was obtained for “area artillery fire in front of advancing lines.” [xlix]

The American method, once area artillery fires and tanks became available, was to pulverize the building they faced and then to assault into the remains.  They used bazookas and flamethrowers against machine gun nests.  They used abundant light suppressive fire weapons, grenades, and mortars, as well as small arms.  Sometimes U.S. assaults failed because of withering fire or counterattacks, in which case troops would pull back and repeat the process.  Tanks and tank destroyers were used in a direct-fire role for the artillery preparation.  Their use beyond that was evidently limited by mines, rubble and the heavy concrete walls of the buildings themselves.  Tanks could not follow infantry into the cellars and onto the roofs.  Americans in Manila evidently learned to use their assets as they went along and used them to full advantage.  Casualties suffered by the 37th Infantry Division when artillery restrictions were first lifted from 10-12 February averaged twenty-six KIA per day.  By the period 21-23 February when the division was fighting at City Hall and assaulting Intramuros,  casualties were down to six KIA per day on average. [l]

The Americans at Manila learned fast.  They used artillery and tanks to the fullest to achieve their objectives with minimal loss of friendly troops’ lives.  The falling friendly casualty rates suggest that American troops between 3 February and 23 February had refined all manner of urban warfare methods, at all operational levels, that allowed them to advance more efficiently at the end than at the beginning.  American troops had superior assets from the start; by the end, they knew how to use them.  Americans won at Manila because they applied a full range of combined arms methods against a static defense.  They got better at it as they went along. 

The Battle of Manila offers many lessons and insights that may be applicable to future instances of urban warfare.  Some of these insights are tactical in nature.  They show how to cope with the enemy force.  Others are civil in nature.  They show how to cope with the civilian population and with objectives relating to the civilian population.  Many of the tactical lessons of Manila we have already explored in examining the methods of Japanese and U.S. forces.  Some of these lessons are applicable to combined arms warfare in general, not exclusively to urban warfare.  Some of the tactical features of Manila, however, are peculiar to cities and likely to recur in operations in other cities.