This was the first indicated change in mission, according to the X Corps command report, since CinCFE’s directive late in October calling for a drive to the border. The amendment “was made necessary,” the report continued, “by the enemy build-up in front of the Eighth Army and the fact that the enemy action had halted the first attempt ... to advance Eighth Army to the border. An estimate of the Eighth Army situation ... fixed the relative combat power as 100,000 UN to 100,000 enemy with UN forces having air superiority and superior artillery support.... The enemy was given an offensive capacity which he could implement with an estimated reserve of 140,000 CCF troops north of the Yalu River. In view of the enemy’s offensive capacity, Eighth Army adopted a conservative plan to make a general advance with the main effort in the center generally parallel to the enemy MSR (Huichon-Kanggye). This course of action was designed to meet any course of action which might be adopted by the enemy. To assist the Eighth Army advance, X Corps was to initiate a main attack to the West from the Chosin Reservoir area, cutting the enemy MSR at Mupyong-ni, and advance in a northwesterly direction to the Yalu River line at Manpojin.”[326] [326] X Corps _WD Sum, Nov 50_, 4–5. By a coincidence it was also on Wednesday, 15 November, that General Smith wrote a letter which foreshadowed future military events. Addressed to General Clifton B. Cates, Commandant of the Marine Corps, this communication made it plain that the 1st Marine Division commander and his staff did not share in the renewed optimism as to the course of the UN war effort. Not only did the Marines accept the possibility of imminent and formidable CCF intervention, but they were making preparations to meet it. So far our MSR north of Hamhung has not been molested, but there is evidence that this situation will not continue.... Someone in high authority will have to make up his mind as to what is our goal. My mission is still to advance to the border. The Eighth Army, 80 miles to the southwest, will not attack until the 20th. Manifestly, we should not push on without regard to the Eighth Army. We would simply get further out on a limb. If the Eighth Army push does not go, then the decision will have to be made as to what to do next. I believe a winter campaign in the mountains of North Korea is too much to ask of the American soldier or marine, and I doubt the feasibility of supplying troops in this area during the winter or providing for the evacuation of sick and wounded. The letter mentioned such preparations as the work done by Marine engineers to strengthen the Hamhung-Hagaru road for tanks and heavy vehicles. Plans had been approved, added General Smith, for an airstrip at Hagaru capable of landing cargo planes for resupply and casualty evacuation.