The Rise of a Promising Strategist

Ma Su entered the historical stage during the turbulent Three Kingdoms period (220–280 CE), a time when the shattered Han Empire gave way to three rival states. As a young scholar-official serving the Shu Han kingdom, Ma Su initially showed great promise. His early career included administrative posts as magistrate of Mianzhu and Chengdu, followed by appointment as governor of Yuexi Commandery. Contemporary records describe him as “a man of exceptional talent who loved discussing military strategy.”

What made Ma Su particularly noteworthy was his close relationship with Zhuge Liang, Shu’s legendary chancellor and military strategist. The two would engage in marathon strategy sessions, often talking through the night about campaign plans and tactical innovations. This intellectual bond mirrored the famous partnership between Cao Cao and his advisor Guo Jia during the preceding warlord era.

The Weight of Expectations

Ma Su carried significant political baggage. His elder brother Ma Liang had been one of Zhuge Liang’s most trusted deputies before dying heroically at the Battle of Xiaoting in 222 CE. This familial connection created both opportunity and pressure—Zhuge Liang clearly saw Ma Su as someone to groom for leadership, perhaps hoping to replicate the successful mentor-protégé relationship he’d enjoyed with Ma Liang.

The stakes became particularly high during Zhuge Liang’s Northern Campaigns against the rival Wei kingdom. In 228 CE, as Shu forces advanced into the strategic Longyou region (modern Gansu), Zhuge Liang made the fateful decision to appoint Ma Su as vanguard commander for a critical defensive operation at Jieting. This assignment represented both a tremendous vote of confidence and a calculated political move—by promoting his protégé over more experienced generals like Wei Yan, Zhuge Liang sought to consolidate his control over Shu’s military establishment.

The Disastrous Decision at Jieting

The Battle of Jieting should have been a straightforward defensive operation. Historical precedent existed—two centuries earlier, general Lai Xi had successfully defended the nearby Lüeyang city against overwhelming odds with just 2,000 troops. Zhuge Liang explicitly ordered Ma Su to fortify Jieting’s existing defenses and hold the position against Wei reinforcements led by the formidable general Zhang He.

Instead, Ma Su made three catastrophic choices:

1. He abandoned the prepared defensive positions in Jieting town
2. He stationed his troops on nearby Southern Mountain, sacrificing access to vital water sources
3. He ignored repeated warnings from his subordinate Wang Ping about these tactical errors

Contemporary military logic favored defending walled positions—especially when outnumbered. By eschewing Jieting’s fortifications, Ma Su surrendered every defensive advantage. When Zhang He’s veteran Wei troops arrived, they quickly severed the Shu army’s water supply, then attacked the dehydrated, disorganized forces. The result was a total rout, with only Wang Ping’s disciplined rear guard preventing complete annihilation.

The Ripple Effects of Failure

Ma Su’s defeat triggered a cascade of strategic disasters:

– Zhuge Liang’s main army, racing to reinforce Jieting, arrived just hours too late
– The loss forced Shu to abandon its hard-won gains in Longyou
– Wei immediately strengthened its northwestern defenses, closing future opportunities
– Shu’s military reputation suffered irreparable damage

In the aftermath, Zhuge Liang executed Ma Su (after the disgraced officer initially fled the battlefield), demoted himself three ranks, and accepted full responsibility. The political fallout extended to other officers—Zhao Yun was demoted, while Zhang Xiu and Li Sheng were executed for poor performance. Only Wang Ping earned promotion for his disciplined retreat.

Historical Lessons and Legacy

The Jieting disaster offers timeless lessons about leadership and warfare:

1. The Perils of Nepotism – Zhuge Liang’s decision to favor his protégé over objectively more qualified commanders proved disastrous. Even Liu Bei had warned that Ma Su “talked beyond his abilities.”

2. Fundamentals Over Flash – Ma Su sought dramatic, unconventional tactics when basic, proven methods would have succeeded. His desire for glory overrode military prudence.

3. The Fragility of Momentum – Shu never recovered the strategic initiative lost at Jieting. Subsequent Northern Campaigns achieved limited success at tremendous cost.

4. Accountability Matters – Zhuge Liang’s willingness to punish himself alongside his officers helped maintain discipline and morale despite the catastrophe.

Historians debate whether Ma Su deserves his reputation as China’s most infamous “armchair strategist.” Unlike the similarly maligned Zhao Kuo (defeated at Changping in 260 BCE), Ma Su had no redeeming final stand—just catastrophic miscalculation. His story endures as a warning about the dangers when intellectual arrogance meets real-world responsibility.

The Jieting debacle also highlights the brutal mathematics of small states—Shu’s margin for error was razor-thin. One mistake could undo years of preparation. In this light, Zhuge Liang’s famous “Memorial on Taking the Field” takes on tragic dimensions—his meticulous plans undone by misplaced trust in one flawed subordinate.

Nearly two millennia later, the phrase “Ma Su at Jieting” remains Chinese shorthand for disastrous overconfidence—a cautionary tale about the gap between theoretical knowledge and practical leadership that resonates far beyond its original military context.