Background
The death of He Jin was the full eruption of the long struggle between the two great factions of consort-kin and eunuchs at the end of the Eastern Han. The novel opens by laying out, through all manner of portents and the chaos of the "Ten Attendants" colluding for profit and selling offices, the broad backdrop of a court growing daily worse and hearts inclined to revolt [c:16144]. He Jin, with the dignity of imperial brother-in-law and General-in-Chief, held military power and was the representative of the consort-kin faction; while Zhang Rang, Duan Gui, and the rest of the Ten Attendants were entrenched in the inner court and deeply relied upon by the Empress Dowager. The moment Emperor Ling died and the young emperor succeeded, a power vacuum opened, and the contest between consort-kin and eunuchs over "who would assist in government" suddenly reached white heat, making a violent clash between He Jin and the eunuch faction inevitable.
Principal Figures
He Jin was the central figure of this tragedy—a failure who held heavy forces yet was irresolute. Yuan Shao was the most resolute hawk, repeatedly urging that the eunuchs be wiped out and rooted up, even proposing to summon outside troops to the capital to coerce the Empress Dowager [c:16149]. Empress Dowager He stood opposite He Jin; of humble origin, she had in earlier years risen to wealth and honor precisely through eunuch support, and so did her utmost to shield Zhang Rang and the others [c:16146]. Zhang Rang, Duan Gui, and the rest of the Ten Attendants were the true operators behind the scenes; well versed in the art of palace survival, they first cut down Jian Shuo as a scapegoat to protect themselves, then used bribes of gold and pearls to ingratiate themselves with He Jin's younger brother He Miao and their mother, Lady Wuyang, dismantling He Jin's resolve layer by layer [c:16149]. Cao Cao, Yuan Shu, and others were the rising new generation of forces emerging in this storm.
Core Issues
The core issue of the whole situation was "how to deal with the eunuchs," and it was precisely on this question that He Jin's fatal weakness was exposed. After executing Jian Shuo, Yuan Shao advocated seizing the momentum to wipe out the Ten Attendants, but He Jin shrank back because of the Empress Dowager's protection, willing only to exterminate Jian Shuo's household and unwilling to widen the blow [c:16146]. This compromise of "removing the chief evildoer and pardoning the rest" is the most dangerous posture in a life-and-death power struggle—it both offended the eunuch faction and failed to cut away its claws and fangs entirely. More fatal still was the plan to summon outside troops to the capital: He Jin's attempt to use the strength of frontier commanders like Dong Zhuo to coerce the Empress Dowager into submission was tantamount to handing over the capital's initiative to a wolfish, tiger-like army—a textbook case of "drawing in the tiger to drive off the wolf."
Political Consequences
He Jin's hesitation gave the eunuchs time to strike back. Seeing the crisis, Zhang Rang and the others laid an ambush and killed He Jin as he entered the palace. With the commander dead, Yuan Shao and Yuan Shu at once loosed their troops into the palace and carried out an indiscriminate slaughter of the eunuchs, plunging Luoyang into chaos of blood and fire. The greatest beneficiary of this internal turmoil was Dong Zhuo, who had already been summoned and was approaching with his troops—he entered the capital amid the chaos, took control of the young emperor, and went on to depose and install rulers and monopolize power, throwing the Eastern Han central government into utter disorder. The death of He Jin was in essence the fuse that touched off "Dong Zhuo's Coup" and the warlord melee that followed.
Counterfactual Speculation
Had He Jin, after executing Jian Shuo, immediately adopted Yuan Shao's counsel and decisively wiped out the eunuchs, would history have been different? With the military power he then held and the support of the court's scholar-officials, a swift purge of the inner court was by no means impossible, and this would have required neither summoning outside troops to the capital nor giving the eunuchs a window to lay their ambush. Stepping back, even had he been unwilling to launch a great slaughter, so long as he did not summon frontier commanders like Dong Zhuo into the capital, the military initiative would have remained in his own hands, and even a eunuch counterstroke could hardly have grown into anything great. He Jin's true tragedy lay in his having neither the resolve to wipe out the eunuchs nor the steadiness to guard the capital region; wavering between the two, he buried the consort-kin faction along with his own life, and indeed the entire central order of the Eastern Han. This episode also became a classic negative lesson for later ages of "nurturing bandits to one's own ruin and inviting the wolf into the house."