▁the ▁Th ais ▁were ▁hel il ift ed ▁out ▁in ▁Operation ▁Sw an ▁Lake . ▁Special ▁Re quire ment ▁ 8 ▁was ▁dis band ed ▁once ▁it ▁was ▁back ▁in ▁Th ailand . ▁ ▁The ▁H m ong ▁L ' Arm ée ▁C land est ine ▁fought ▁three ▁successful ▁campaign s ▁during ▁ 1 9 6 9 : ▁Rain d ance , ▁Operation ▁Off ▁Bal ance , ▁and ▁K ou ▁K iet . ▁By ▁the ▁close ▁of ▁the ▁latter , ▁the ▁Secret ▁Army ▁had ▁dw ind led ▁to ▁ 5 , 0 0 0 ▁to ▁ 5 , 5 0 0 ▁H m ong ▁effect ives ; ▁they ▁were ▁faced ▁by ▁ 2 2 , 0 0 0 ▁Commun ist ▁troops . ▁The ▁H m ong ▁man power ▁pool ▁was ▁nearly ▁dry , ▁as ▁only ▁te en agers ▁and ▁ag ing ▁men ▁were ▁still ▁available . ▁By ▁comparison , ▁there ▁was ▁an ▁essentially ▁bottom less ▁pool ▁of ▁ 1 0 , 0 0 0 ▁rep lac ements ▁per ▁year ▁available ▁for ▁the ▁Vietnam ese ▁Commun ists . ▁ ▁During ▁the ▁Vietnam ese ▁Camp aign ▁ 1 3 9 , ▁which ▁threatened ▁the ▁existence ▁of ▁V ang ▁Pa o ' s ▁L ' Ar mee ▁C land est ine , ▁ 3 0 0 ▁Th ai ▁art illery men ▁of ▁Special ▁Re quire ment ▁ 9 ▁arrived ▁at ▁Long ▁T ien g . ▁They ▁arrived ▁on ▁ 1 8 ▁March ▁ 1 9 7 0 , ▁when ▁V ang ▁Pa o ' s ▁res