 The third phase received the least consideration , but naval planners were aware that Singapore was too far from Japan to provide an adequate base for operations close to Japan . Moreover , the further the fleet proceeded from Singapore , the weaker it would become . If American assistance was forthcoming , there was the prospect of Manila being used as a forward base . The idea of invading Japan and fighting its armies on its own soil was rejected as impractical , but the British planners did not expect that the Japanese would willingly fight a decisive naval battle against the odds . They were therefore drawn to the concept of a blockade . From personal experience they were aware of the impact it could have on an island nation at the heart of a maritime empire , and felt that economic pressure would suffice . 
