While the Japanese were able to advance and encircle the formations of British 14th Army, they were unable to defeat those same forces or break out of the jungles along the Indian frontier. The Japanese advance stalled. The Japanese, who had a contempt for British and Indian troops based on their performance in 1941–42, refused to give up even after the monsoon started and large parts of their army were wrecked by conducting operations in impossible conditions. The initial Japanese plan was to capture Allied stocks of food, medicine and fuel to sustain their advance, but they failed to capture any stockpiles. As a result, their units took unsupportable casualties and were finally forced to retreat in total disorder in July 1944, leaving behind many dead from hunger and disease as well as their injured. Of the 150,000 Japanese soldiers who invaded India in March 1944, almost all of them were dead by July 1944 as Slim had inflicted the largest defeats that the Japanese had suffered up to this point in the war. The Indian Army remained loyal, and under its British officers fought much better than the Indian National Army. After Imphal and Kohima, the American historian Gerhard Weinberg noted for the Japanese their "... only hope in the area was propaganda by Bose, not much of a substitute for their lost Japanese 15th Army".