Type 97 Chi-Ha

By the mid-1930s the Imperial Japanese Army needed a new medium tank to replace its ageing Type 89. Japan's armoured doctrine was shaped by the wars it expected to fight — campaigns of conquest across China and the Pacific, against enemies with little armour of their own. The tank's job, as the Army saw it, was to support the infantry, overrun positions and exploit breakthroughs, not to duel with other tanks.

Two designs competed: a cheaper, lighter prototype favoured by the budget-conscious, and the larger, more capable Chi-Ha from Mitsubishi. The outbreak of full-scale war in China in 1937 settled the argument — money was suddenly available, and the more powerful Chi-Ha was adopted as the Type 97. It went on to become the most important and most numerous Japanese tank of the war.

The Chi-Ha reflected its support role in every line. Its original 57 mm gun was a low-velocity weapon, excellent for firing high-explosive shells at bunkers, buildings and infantry, but poor at penetrating armour — exactly the trade-off the Army wanted for fighting in China. Its armour, at most around 25 mm, was thin even by the standards of 1938 and offered protection only against machine guns and light cannon.

It did have genuine virtues. It was reasonably fast and mobile, mechanically reliable, and powered by an air-cooled diesel engine well suited to the dust and heat of Asia and less prone to catching fire than petrol units. For the colonial and anti-infantry warfare Japan planned to wage, it was a sound and effective vehicle.

The problem came when Japan met enemies with modern tanks. Against Soviet armour at Khalkhin Gol in 1939, and later against American Shermans in the Pacific, the Chi-Ha's weak gun and thin armour were brutally exposed. The Army's answer was the Shinhoto Chi-Ha — 'new turret' — which mounted a higher-velocity 47 mm anti-tank gun in a larger turret, giving the tank at least a fighting chance against enemy armour.

The most important variant was the Type 97-kai Shinhoto Chi-Ha, with its new turret and 47 mm gun, which became the standard Japanese medium tank for the later war years and the best chance Japanese crews had against Allied armour. The original 57 mm-gunned version continued in service throughout.

The reliable Chi-Ha chassis was also widely adapted. It served as the basis for self-propelled guns such as the Type 1 Ho-Ni tank destroyer and the Type 4 Ho-Ro assault gun, as well as engineer vehicles, recovery tanks and command vehicles — making it the workhorse foundation of Japan's armoured forces much as the Panzer IV chassis was for Germany.

The Chi-Ha saw its first major action in China, where against poorly-equipped Chinese forces it performed exactly as intended, supporting infantry and overrunning positions with little to oppose it. In the opening Japanese offensives of 1941–42 it rolled through Malaya, the Philippines and Burma, helping win the stunning early victories that carried Japan across South-East Asia.

For the war Japan expected to fight, the Chi-Ha was adequate. Its 57 mm gun was a short, low-velocity weapon meant to support infantry against fortifications and enemy foot soldiers, not to fight other tanks — a reflection of a doctrine that saw armour as an infantry-support arm. Against the poorly-equipped opponents of 1937–42 that was enough; against a first-class tank army it was not.

But as the war turned, the Chi-Ha was increasingly outclassed. In the island battles of the Pacific it met the American M4 Sherman and was hopelessly outgunned and out-armoured — Japanese tanks were frequently destroyed in moments, and were often dug in as static pillboxes rather than risked in open battle. The decisive armoured clash against the United States never really came; Japan simply lacked the tanks and the doctrine to fight one.

By 1945 large numbers of Chi-Has were being held back in Japan and Manchuria against the expected invasions. In the final days of the war they faced the massed, modern armour of the Soviet offensive into Manchuria, where they were swept aside with ease — a stark final demonstration of how far Japanese tank development had fallen behind.

The Type 97 Chi-Ha was a competent tank for the war Japan planned to fight, and a poor one for the war it actually faced. Designed for infantry support and colonial campaigns against lightly-armed enemies, it did that job well in China and in the early Pacific conquests, and it remained the backbone of Japanese armour to the end.

Its weakness was strategic as much as technical. Japan poured its industrial strength into ships and aircraft and never treated the tank as a war-winning weapon, leaving the Chi-Ha to soldier on, lightly armed and thinly armoured, long after the Americans, Soviets and Germans had moved far beyond it. It is remembered less as a great fighting machine than as the symbol of a nation that simply chose to fight its war by other means.

• Steven J. Zaloga, Japanese Tanks 1939–45 (Osprey, New Vanguard).
• Leland Ness, Rikugun: Guide to Japanese Ground Forces 1937–1945 (Helion).