When the US, having bypassed the fortress atoll of Truk, decided to strike directly against the Marianas and decisively defeated the IJN's counterattack in the Battle of the Philippine Sea, the inner perimeter of the Japanese Empire became threatened. Having done little to strengthen its reserves, IGHQ in June and July 1944 sent seven divisions, the 1st, 8th, 10th, 24th, 9th, 28th, and 2nd Armored, into the fray, joined by an eighth, the 23rd (veterans of the Khalkhin Gol fighting in 1939), in October. Of the above, all except the 9th, bypassed on Formosa, and the 28th, on Miyako Jima, avoided being devastated by battle, starvation, and disease during the brutal combat in the Philippines and Okinawa. The decision to reinforce Formosa was of particular consequence for Japan. Recognizing that island's strategic importance with regard to the flow of vital raw materials to the mainland, Tokyo resolved to prevent it from falling into Allied hands at all costs. Thus, in December 1944 and January 1945, the 12th and 71st Divisions were ordered there from Manchuria to reinforce the two-division garrison that had recently been augmented by the Kwantung 9th Division that arrived via Okinawa. The loss of the 9th Division was seen as nothing less than a body blow for Okinawa's 32nd Army commander, Lieutenant General Mitsuru Ushijima, who warned: "If the 9th Division is detached and transferred, I cannot fulfil my duty of defending this island." In the end, because of the American island-hopping strategy, none of the five divisions (including three from the Kwantung Army) ever fired a shot against an American invasion and were left to wither on the vine.