Holding the intelligence Du Ruhui had personally delivered, Li Shimin pondered it briefly, then issued an order.
"Summon Pei Shiqing."
The arrival of envoys from Wa shocked Li Shimin more than a little.
In his current grand plan, defeating Tuyuhun, opening the Hexi Corridor, and extending Han power into the Western Regions were the foremost priorities.
As for the Korean Peninsula, the Wa archipelago, the islands of the southern seas, and those faraway lands praised as heaven's own treasure vaults, any attempt to manage them required a powerful navy as a prerequisite.
But the Tang navy at present… even with Lingnan Circuit and Jiangnan Circuit backing it, capturing Yizhou Island alone remained difficult. Forget projecting power across the Eastern Sea.
So for now, Li Shimin had set those ambitions aside.
On one hand, he was establishing a Mathematical Pavilion in Chang'an to study mathematical classics, while also exploring how to apply them to governance and maritime affairs.
On the other hand, he had recalled a group of naval officers to Chang'an, combining them with younger commanders led by Liu Rengui, to undergo short-term study together. They would learn maritime affairs, understand foreign peoples, study sea conditions, master sail handling, and read the winds. After half a year, they would return to the coasts to jointly command the navy.
Lastly, there was Hou Junji. With the Duke of Lu as the leader, they would assemble fleets, test new ships, trial new methods, summarize gains and losses, and ultimately incorporate everything into the naval system.
Yet now the Wa people had sent envoys.
This truly lay outside Li Shimin's plans and even felt unexpected.
Had they not only sent envoys several years after the Battle of Baekgang in history?
After a moment's thought, Li Shimin dismissed Du Ruhui, instructing him to further organize detailed information on this Wa delegation.
At the same time, he summoned Pei Shiqing, the man most familiar with Wa.
In the Tang court, when it came to understanding Wa's past, none surpassed this former Sui dynasty envoy to Wa.
After Wei Zheng brought his past to light, Li Shimin had promoted Pei Shiqing from the comfortable post of Director of Carriages to the more practical position of Director of the Secretariat. He had personally summoned him, questioned him about Wa customs, and ordered him to record his observations.
Now that Wa had sent envoys for the first time since the founding of Tang, summoning Pei Shiqing was the simplest and most direct course.
Soon enough, the palace attendants swiftly escorted Pei Shiqing into the hall.
Though this was only the second time Li Shimin had met this man who once braved the seas to Wa, seeing him in person still drew an inward sigh from the emperor.
A truly fine piece of jade, perfectly suited to be an envoy.
Bearing mattered greatly for a diplomat, and Pei Shiqing excelled in this regard. Though nearing fifty, he stood tall with a natural Han dignity, composed and imposing, commanding respect without anger.
That bearing, however, crumbled the moment he faced Li Shimin.
He bowed slightly and saluted.
"Your Majesty."
Li Shimin went straight to the point.
"Wa has sent envoys and they have reached Hebei Circuit. What does my minister think should be done?"
Though many years had passed since his return from the Eastern Sea, Pei Shiqing clearly understood the role he was expected to play after his reinstatement. He answered almost without hesitation.
"The Wa people have come seeking the culture of our Central Plains."
"After Your Majesty previously summoned me, I learned through inquiries that in the sixth year of Wude, several monks who had come to China with Wa envoys during the Sui dynasty left their temples and returned home."
"It has now been eight years. Those monks must have spread the fame of Great Tang upon their return, prompting Wa to imitate the practices of the Daye era and send envoys to study our rites."
"In the past, when I traveled in Wa lands, their people were savage and ignorant of propriety. Their king was crude and shameless, styling himself the Son of Heaven of the land where the sun rises, a phrase arrogant and taboo-breaking."
"Now that Your Majesty has punished the wicked, captured Jieli Khan before the palace, and spread Tang's might across the desert south and to Liaodong, the Wa envoys must surely tremble in fear before imperial authority. How to accept or reject them lies in Your Majesty's judgment."
As Pei Shiqing spoke with calm confidence, Li Shimin's gaze drifted slightly when he heard the words "shameless."
After learning of Pei Shiqing, Li Shimin had ordered the Hundred Cavalry Bureau to search for other members of the original Sui embassy. Not out of distrust, but to assemble a fuller picture.
Few were found due to the passage of time, but the Bureau returned with a rumor.
It was said that when the Sui embassy reached Wa, the Wa people, most of whom were under five chi in height, regarded the seven-chi-tall Han envoys as gods.
The Wa queen supposedly sent a close royal woman to the Sui envoy residence, wishing to retain their bloodline.
Li Shimin had once dismissed this as absurd. Yet now, knowing Wa royal conduct and seeing Pei Shiqing's imposing presence, it did not seem entirely impossible.
"Your Majesty?"
"Cough, cough."
Pei Shiqing, seeing no response, called out. Li Shimin returned to himself, coughed twice to hide his lapse, and nodded in approval.
Standing together in Ganlu Hall, Li Shimin pondered for a moment, then asked directly.
"If one wished to permanently settle the Wa problem, what method would you advise?"
The question caught Pei Shiqing off guard.
"Your Majesty…"
After gathering his thoughts, he answered carefully.
"The Wa people are contemptible and lack such capacity."
This assessment was not wrong. Pei Shiqing had seen Wa firsthand, and his judgment was reasonable.
Only because Li Shimin had been tempered by later knowledge did he view the matter differently.
Eliminating Wa troubles was not difficult. Build the Tang navy, seal their ports, cut their sea routes, leave the people ignorant, then secretly support internal factions to overthrow their king. Let the islands fracture and war endlessly. Peace for centuries could be ensured.
But now that Li Shimin understood the importance of the oceans, he also understood the value of that long chain of islands.
If China could one day establish naval garrisons there, the Eastern Sea could become an inland sea like Rome's Mediterranean, keeping enemies beyond the gates and securing maritime borders.
Not to mention that the Wa islands held mountains of silver, supplying nearly thirty percent of the world's silver. Though their wealth did not match those distant treasure islands, their location alone made them superior.
Though he did not know whether Liu Rengui would succeed in landing on Wa during his reign, Li Shimin believed such century-spanning plans were best prepared early.
Pei Shiqing argued his point, then felt his tone might be too firm and sought to soften it. But when he looked up, he saw the emperor had turned away, hands clasped behind his back.
At the same time, Pei Shiqing noticed the furnishings of Ganlu Hall, all unfamiliar. His gaze was seized by a massive map on the right side of the hall, immediately spotting the word Chang'an marked upon it.
A map?
But how could it be like this…
Hard to describe, yet his past experience sketching sea charts amid Eastern Sea storms told him that the Liaodong seas were depicted with uncanny accuracy.
If this were true, it was astonishing beyond words.
Li Shimin's voice sounded quietly.
"Do you know that the oceans cover seventy percent of this world, and that survival in the future begins with guarding the seas?"
"Do you know that we dwell upon a globe, and that beyond the stars there are barbarians who would invade it?"
"Do you know that to make all under heaven submit, one must command the seas?"
The voice grew more intense, his gaze burning as it fixed on Pei Shiqing.
Reason told the veteran official that he should summon physicians at once. Emotion told him that the emperor's words must have purpose.
After a painful hesitation, Pei Shiqing spoke slowly.
"Your Majesty's words, could they be…"
"Sit," Li Shimin said curtly, motioning him down. Then he began.
"This matter goes back a very long way."
As the small lecture in Ganlu Hall began, Yan Lide of the Directorate of Works stared at a cracked foundation base with deep regret.
"The difference between volcanic ash and slag is truly this great?"
A deputy director beside him asked curiously.
"What is volcanic ash?"
They were familiar with each other, having both served as deputy directors the year before. Yan Lide had since risen in favor and shed the word deputy. Yet he never forgot his former colleagues, and relations had only grown closer.
Yan Lide answered matter-of-factly.
"Volcanic ash comes from volcanoes."
This explanation only deepened the confusion.
What was a volcano?
Yan Lide himself did not know. He clapped his hands decisively.
"Enough. If this will not work, adjust the ratios of soil, slag, and lime and test again."
At his order, everyone set aside their curiosity and moved to work.
Yan Lide remained, seized an iron rod, and smashed along the cracks in the cement base, breaking it apart to examine the interior.
Feeling the painful recoil through his hands, he gained a rough understanding of why this substance was prized in later ages and called black technology.
Perhaps that meant superior technology.
The deputy director came over to help, prying the cement apart with another iron rod so Yan Lide could observe.
With a grateful smile, Yan Lide studied the interior and sank into thought.
All the ingredients for cement were abundant in Chang'an. With the combined efforts of the Directorate, workable ratios were soon found.
Yet the cracking after drying continued to plague him.
Seeing his troubled look, the deputy director spoke casually.
"Perhaps it lacks beams and supports?"