For Liu Bei, the irrational Emperor Li Zhi possessing an army of three hundred thousand was not particularly enviable.
After all, Kongming had explained it to him more than once, patiently breaking it down in detail: when commanding an army exceeding one hundred thousand, the difficulty was never the number of men.
Logistical supply, communication between superiors and subordinates, how orders were effectively transmitted, how to make the army move in battle as smoothly as one's own limbs—these were the true challenges.
Yet none of these difficulties were insurmountable.
Training officials, ensuring officers were literate, establishing standardized systems of command using flags and drums, recruiting more staff officers to accompany the army—these were all ideas that often came up in long discussions.
The command of large armies could be cultivated and replicated.
But the victories of famous generals—those could never be replicated.
Like the Champion Marquis, able to penetrate deep behind enemy lines without losing his way, and still fight fiercely battle after battle.
Like Li Jing, launching a snow-night raid that swept the enemy's very hearth and courtyard, and whose predictions of the enemy were never wrong.
At this moment, Liu Bei understood more deeply the saying passed down by later generations: that the significance of a great general lies in accelerating the course of history.
Ten thousand men could achieve what three hundred thousand could, in less time, with less grain consumed, and with far better results.
[Lightscreen]
[Under the reign of the Heavenly Emperor Li Zhi, the decline in the Tang army's combat effectiveness was plainly visible.
Some attributed this to the gradual collapse of the fubing system, claiming that Tang's strength under Li Shimin was due to the fubing system being intact.
But in truth, by the later years of Li Shimin's reign, the fubing system had already fallen behind the times. The most typical example was Xue Rengui.
Xue Rengui was not a fubing soldier, but a recruited soldier—known in Tang times as a zhengren.
The "Basic Annals of Taizong" records it clearly: "Armor-clad soldiers were levied across the realm; one hundred thousand were recruited and dispatched toward Pyongyang to attack Goguryeo."
Why was this done? Because the fubing system simply could not supply enough men.
The fubing system resembled a soldier-farmer arrangement: soldiers were farmers in peacetime and soldiers in wartime, exempt from taxes, but required to serve a fixed number of days each year.
For example, within five hundred li of Hulao Pass there might be a military prefecture of one thousand men. According to Tang regulations, this thousand-man prefecture had to be divided into five groups of two hundred men, each serving one month in rotation—five rotations in total.
Such a system became completely inadequate once Tang began rapid territorial expansion.
As territory expanded, the places where fubing soldiers served were often thousands of li away from their home prefectures. Each term of service might take a year, or even longer.
Moreover, wars during the Zhenguan era were frequent. It was common for a fubing soldier to finish one year of service only for another war to begin, forcing him to rush to a new battlefield, making rotation calculations extremely complex.
Secondly, under the Zhenguan emphasis on military merit, the fubing system actually limited the scale of mobilization.
Still using the five-rotation example: in the tenth year of Zhenguan, Li Shimin established 634 military prefectures across the realm, divided into upper, middle, and lower grades. Upper prefectures had 1,200 men, middle 1,000, and lower 800.
From this, one can roughly estimate that there were about 600,000 fubing soldiers in the tenth year of Zhenguan. Under the five-rotation rule, the maximum number that could be mobilized at any one time was 120,000.
These 120,000 had to garrison the frontiers and protect the capital. In the end, the number that could actually be dispatched to fight was only about forty to fifty thousand.
If one further accounts for travel time and mandated rest between rotations, then in the case of consecutive campaigns, the number of fubing soldiers that could be sent out might drop to around thirty thousand.
It was precisely for this reason that Second Phoenix began recruiting soldiers when attacking Goguryeo—and ultimately drew a gold-rarity card like Xue Rengui.
"Those who were willing were taken; recruiting ten yielded a hundred, recruiting a hundred yielded a thousand. Those unable to join the army all sighed in resentment."
This is how recruitment was recorded, showing just how effective it was. After all, for Tang commoners, joining the army was not about a few scraps of pay—everyone was aiming for military merit.
And during the Liaodong campaign, the combat effectiveness of these recruited soldiers was plain for all to see.
The God of Slaughter Xue Rengui need not be mentioned—he was the best possible endorsement of the recruitment system.
A classic example was the Battle of Baiyan City. The city's lord surrendered, then rebelled again, enraging Li Shimin, who immediately decreed that after the city fell, he would take none of the captives or treasure—all would be awarded to the soldiers.
Under such incentives, Baiyan City fell within three days. During the battle, Qibi Heli even led just eight hundred men to repel ten thousand reinforcements from Wugu City. The combat power of recruited soldiers was unmistakable.
After the Goguryeo war temporarily ended, although the two battlefields were very close, Li Shimin still issued an edict forbidding anyone who had participated in the Goguryeo campaign from joining the campaign against Xueyantuo.
This decree could be said to let the people recover—or it could be said to ensure that the fubing soldiers waiting eagerly at home would also get a share of the spoils.
But all this back-and-forth only demonstrated one thing: rather than saying the fubing system gradually collapsed, it would be more accurate to say it gradually ceased to suit Tang's national conditions, which increasingly required campaigns spanning thousands of li.]
Although no edict had yet been issued to reorganize the military prefectures of the realm, Li Shimin had to admit:
"This conflict here is truly a hidden danger."
"The military prefectures are mostly established in Henan, Hebei, Hedong, and Guanzhong. If it is like last year's campaign against Illig Qaghan, the distance is only a thousand li or so."
"But if one were to levy fubing soldiers from Huainan Circuit to campaign in the Western Regions, the round trip would likely take no less than a year."
Yet you could not simply ignore the fubing soldiers of Huainan Circuit entirely.
For if Western Region campaigns drew only from nearby Guanzhong Circuit, then once the Western Regions were pacified, Guanzhong soldiers would likely each hold multiple rotations of merit—while the fubing soldiers of Huainan and Hebei would turn green with envy.
Thus, under such circumstances, Du Ruhui grew curious:
"I wonder what the military system of later ages is like?"
Li Shimin, having immersed himself in warfare for many years, was surprisingly unconcerned:
"No matter what military system is used, in the end it only seeks to instill in soldiers the will to fight."
"The strength of the Zhenguan fubing lay in certain reward for merit and certain punishment for fault; commanders dared to lead from the front, and all were willing to risk their lives for the state."
"Those who can achieve this—whether fubing or recruited soldiers—are elite troops."
"Those who cannot—no matter how many military prefectures they have—are useless."
It was both an answer to Du Ruhui and Li Shimin's own self-questioning.
At this moment, Li Shimin recalled the later army whose soldiers bore the word "people" before their name, recalled how that army could march straight toward natural disasters.
He vaguely understood something—and recalled a question he had once asked himself long ago:
"What makes a strong army?"
Li Shimin answered himself:
"Dao is that which aligns the people's will with that of their superiors, so they may face death together, live together, and fear no danger."
Li Jing, who knew The Art of War by heart, explained to the still-befuddled Su Dingfang:
"Sunzi said there are five methods by which strong armies achieve victory. First, strict laws and discipline; second, wise and courageous commanders; third, full understanding of terrain; fourth, the ability to seize timing."
"These four are not difficult. What His Majesty speaks of is the fifth."
As soon as Li Jing spoke, Su Dingfang wanted to roll his eyes. Not difficult?
Well—perhaps not for you, sir.
Su Dingfang also remembered that this was the opening line of The Art of War.
Precisely because it was the opening, people often overlooked it, focusing instead on later chapters on strategy, momentum, emptiness and fullness, and military contention.
Sunzi spoke simply, but Su Dingfang now understood:
"This fifth—attaining the Way—how difficult it is. Who could achieve it?"
When the will of the people aligns with that of their rulers—when soldiers and commoners share the same intent—then the army can face life and death without fear.
By the light screen's account, even the Zhenguan fubing fought merely for military merit, far from truly attaining the Way.
Du Ruhui also recalled that army which charged toward disaster, and sighed softly:
"The army of later ages—that is an army that has attained the Way."
Su Dingfang and Li Shiji found it hard to believe.
Li Shimin smiled, indicating his understanding.
[Lightscreen]
[Thus, the decline in Tang military strength had little to do with whether soldiers were fubing or not, and far more to do with Li Zhi.
Seeing how effective his father's recruitment had been, Li Zhi followed suit.
The difference was that under Li Zhi, the combat effectiveness of recruited soldiers declined steadily. Strong, able-bodied recruits became fewer and fewer; in the later period, even when recruiting the old and weak, quotas still could not be filled—forming a stark contrast with Li Shimin's era.
Eventually, Liu Rengui could no longer stand it and submitted a memorial laced with biting sarcasm. He identified a key turning point:
The fifth year of Xianqing—660 CE.
That year, Su Dingfang pacified the Three Kingdoms of the Pamirs and returned in triumph. During the distribution of rewards, Li Zhi did something decidedly improper:
For soldiers who died in the expedition, no merit was granted, and their cases were no longer even reviewed.
One reason soldiers under Li Shimin dared to give their lives was that even in death, as long as merit had been earned, it could benefit their families. Under Li Shimin, special envoys were even sent to console bereaved families and honor the fallen spirits.
Li Zhi abolished all of these benefits.
Later, during the campaigns against Baekje and the siege of Pyongyang, Li Zhi went further: not only were the dead unrewarded, even the living had their merits docked.
Thus, after 660, every Tang conscription reversed the scene of Li Shimin's time:
The strong, wealthy, and well-connected exerted every effort to bribe and hide, seeking only to avoid conscription.
Those without money or connections—even the old and weak—were forcibly recruited into the ranks.
Under such conditions, how could Tang's combat effectiveness not decline?
Throughout Gaozong's reign, every war relied on recruitment, and the numbers grew ever larger. After the defeat at Dafeichuan, Li Zhi likely reflected in pain:
I still haven't recruited enough troops!
So in one stroke he recruited three hundred thousand men and handed them to Pei Xingjian—simply to avoid losing.
It was fortunate that Pei Xingjian truly had the skill to organize three hundred thousand troops in orderly fashion.
Had it been anyone else, before even meeting the Turks in battle, these uneven Tang troops might have collapsed their own logistics.
And why did Li Zhi suddenly become so miserly? Because he was saving money for a grand purpose:
He intended to perform the Fengshan sacrifices in his father's stead.
Gaozong and Empress Wu began preparations for the Fengshan rites in 664, and only formally conducted them in early 666.
This journey was the largest vanity project since the founding of Tang.
Barely a month after the Fengshan, having drained the state treasury dry, Li Zhi formally issued an edict:
Mint new coinage. Abolish the old.
He was going to take money from the people.]