From
毛泽东《清平乐·六盘山》 (Mao Zedong, 1935), written near the end of the Long March:
天高云淡,
望断南飞雁……
今日长缨在手,
何时缚住苍龙? (Sky high, clouds thin, my gaze follows the south-flying geese... today the long cord is in my hand - when shall I bind the blue dragon?)
长缨 alludes to
《汉书·终军传》 where the young official Zhong Jun asks for a 'long cord' to tie up the king of Nanyue; here, the enemy is Japan.