_Confidence of UN Command_ General MacArthur did not appear to be shaken by EUSAK G-2 reports during the third week of November which called attention to a formidable CCF build-up on both sides of the Yalu. On the contrary, a UN order of the 20th, giving directions for the conduct of troops at the border, indicated that an occupation rather than a fight was expected: Elements of minimum size only will be advanced to the immediate vicinity of the geographical boundary of Korea. No troops or vehicles will go beyond the boundary between Korea and Manchuria, or between Korea and the USSR, nor will fire be exchanged with, or air strikes be requested on forces north of the northern boundary of Korea. Rigid control of troop movements in vicinity of northern boundary will be exercised. _Damage, destruction or disruption of service of power plants will be avoided._ No personnel, military or civilian, will be permitted to enter or leave Korea via the Manchurian or USSR border. Commanders will insure that the sanctity of the international border is meticulously preserved.[347] [347] CG X Corps msg X12811, 20 Nov 50. Italics added. The italicized sentence emphasizes an assumption which had made converts in high State Department as well as Defense circles in Washington. The Chinese, according to this conjecture, were concerned chiefly with defending their Manchurian frontier and guarding the power complexes along the Yalu. As evidence, it was pointed out that early in November the Sinuiju radio described the CCF troops crossing the river as a “volunteer corps” for the protection of the hydro-electric plants along the Yalu serving Mukden, Dairen and Port Arthur. Proceeding from this premise, it was a logical conclusion that if no provocation were given these forces, a large-scale fight might be avoided.[348] [348] See Memo Chairman JCS to SecDef: “Chinese Communists Intervention in Korea,” 9 Nov 50; and Truman, _Memoirs_, II, 372. General MacArthur, after receiving a qualified permission to bomb the Yalu bridges, had enjoined UN airmen not to violate territory or air space on the other side of the river. This meant that the bomber crews must take much greater risks, since their restricted axes of approach and flight paths were known to enemy antiaircraft gunners in advance. Moreover, CCF jet fighters could attack and retire to the sanctuary of Manchuria when hard-pressed.[349] [349] JCS msg 95949, 6 Nov 50; CinCFE msg CX 68411, 7 Nov 50; Schnabel, _Korean Conflict_. See also Karig, _Korea_, 376–378.