The one remaining psychological hurdle was the myth of Japanese invincibility in the jungle. To lay this to rest, Slim planned a campaign where he would enjoy such numerical superiority that he was bound to win; a single victory of this sort would prick the ‘Japanese complex’. This was why he returned to the scenes of British humiliation in early 1943 and ordered another offensive in the Arakan. Stilwell and other American commentators thought this pointless, at least if there was no simultaneous amphibious operation farther south, but they missed the point, which was that Slim was seeking out an easy victory. The one obvious card the Allies had in Burma was numerical superiority. In 1943 the Japanese had five divisions there, which would increase to seven in early 1944 and later to eight, plus four divisions of their Thai allies. Thus far Slim was amply fulfilling one aim of Allied policy, which was to draw enemy manpower away from the Pacific theatre. Against this, even leaving Chiang’s immobile Y-force out of the picture, the Allies could pit the three Chinese divisions Stilwell had trained at Ramgarh – 35,000 men in all – plus six British divisions and auxiliaries, not counting the Chindits and their auxiliaries. In the Arakan Slim was aiming at a two-to-one local superiority, which he hoped would be buttressed by a similar discrepancy in heavy armour and airpower. His 15 Corps would attack the so-called ‘Golden Fortress’ across the Mayu range – a system of defences consisting of interlocking bunkers and built around three distinct bastions: a western approach at Razabil, an eastern approach at Letwedet, and the strongest position of all, the centre, based on the labyrinth of tunnels the British had encountered the year before and which had hitherto been considered impregnable. Slim’s plan was that 15 Corps would advance to the Maungdaw–Buthidaung road and would then bifurcate, with 5 Indian Division attacking Razabil while 7 Indian Division took Buthidaung and assailed the Letwedet bastion from the rear; both divisions would then unite for the attack on the tunnels in the centre. Careful preparations were laid. A road was built over the Ngakyedauk pass in the Mayu range, and where the pass entered the valley at Sinzweya, in a flat area of dried-up paddy fields some 1,200 yards square, corps headquarters was set up – a farrago of buildings, arsenals, petrol dumps, a mule station, an officers’ shop, even a military hospital and soon dubbed the ‘Admin Box’.
Slim had gathered around him a cadre of trusted officers who knew his methods and had listened carefully to his lessons about concentration of force so as to have overwhelming local superiority, the crucial role of tanks, the importance of never attacking on a narrow front and the need constantly to be on the lookout for Japanese outflanking movements. A key part of his doctrine was the ‘hammer and anvil’. Adopting the basic idea of the bunker, he aimed to construct defensive positions in places the enemy had to attack to keep their lines of communication open. Heavily defended, such positions would form the anvil against which the enemy would waste their forces in vain, until the time came for Slim to send in the reserves as the hammer that would deliver the coup de grâce. Three additional factors made Slim confident of success: the Japanese habit of committing all their troops and not retaining a reserve; their reluctance to admit a mistake and cut their losses; and their appallingly idiotic habit of carrying their battle plans and marked maps into combat, so that when the British captured these documents they knew enemy intentions in detail. All these ideas Slim had often communicated to his inner circle, essentially ‘Punch’ Cowan, Philip Christison, Geoffrey Scoones, Frank Messervy, H.R. Briggs, C.E.N. Lomax, Douglas Gracey, Ouvry Roberts, Steve Irwin and Alfred Snelling, his supply and commissariat officer. It was all the more amazing, then, that when the campaign opened in January 1944, Christison, commanding 5 Indian Division, launched exactly the kind of frontal assault on Razabil that had proved so disastrous the year before. Perhaps overconfident after a massive USAAF air assault and a huge tank and artillery barrage, he sent in the infantry, who made no progress against the bunkers. Barbed wire, bamboo stakes and withering fire from pillboxes halted the tanks and heavy artillery in their tracks. From their nests, Japanese machine-gunners doled out fearful damage. Inwardly cursing Christison, Slim was in a difficult position, for if he intervened he would come across as a micromanager in the mould of Noel Irwin; he would be doing to Christison what Irwin had done to him in 1943. It was, he concluded, Christison’s battle, and he just hoped and prayed he would see sense. Fortunately Christison and Briggs recovered from their mistake and on the second assault moved to the Slim orthodoxy of guile, hooks and encirclement, forcing the Japanese to counterattack. But after five days (26–31 January), the Japanese bunkers still stood firm. At the end of January Christison switched his attentions from Razabil to Buthidaung and Letwedet.