The President of the United States of America, under the provisions of the Act of Congress approved July 9, 1918, takes pride in presenting the Distinguished Service Cross (Posthumously) to Colonel (Infantry) Allan Duard MacLean (ASN: 0-18229), United States Army, for extraordinary heroism in connection with military operations against an armed enemy of the United Nations while serving with Commanding Officer of the 31st Infantry Regiment, 7th Infantry Division. Colonel MacLean distinguished himself by extraordinary heroism in action against enemy aggressor forces near the Chosin Reservoir in North Korea during the period 27 through 29 November 1950. On the afternoon of 27 November 1950 the regiment was proceeding north to the Yalu River, and Colonel MacLean, heading a small party, went forward to reconnoiter a route of advance. After considering the terrain, road conditions and overall tactical situation, he established positions for the night on the southern tip of the reservoir and located his command post between two defensive perimeters. The unit successfully repelled a vicious assault in the early hours of 28 November 1950, and at daybreak, Colonel MacLean ordered readjustment of the perimeter to employ a natural defensive feature while denying the enemy a route to the south and friendly supply installations at Hagaru-ri. Despite continued sniper fire, he moved between the two groups throughout the day to insure proper coordination of forces and maintained his command post with the most forward elements to direct operations. The enemy again attacked in great strength throughout the night, but was repulsed by the skillful defense tactics employed by Colonel McLean. The heavy night fighting seriously depleted the ammunition and with enemy activity increasing, he ordered consolidation of the two groups at approximately 0430 hours the following morning. The wounded were placed on vehicles near the front of the column and after proceeding about one hundred and fifty yards Colonel MacLean, spotting a physical roadblock at a bridge, immediately deployed troops to a hill east of the vehicles to provide covering fire and fearlessly advanced alone to neutralize this new threat and was last seen in close grips with a hostile group. For three days, through snowstorms and under constant heavy shelling, he held his combined force together, dominating and controlling the critical situation through the force of his heroic example. The extraordinary heroism displayed by Colonel MacLean on this occasion reflects the greatest credit on himself and is in keeping with the high traditions of the military service.