The road from Chang'an to Tongguan may not be accurate, to be exact, it should be from Chang'an to Luozhou.

This is one of the most important transportation routes in Datang.

In the case of external warfare, perhaps the role of this path is not as important as imagined, but when it comes to internal development, this passage is crucial.

At present, the main traffic road connecting the north and south is the Grand Canal, which was built in the previous dynasties, but the Grand Canal can only go to Luoju.

The official road from Luozhou to Chang'an is the busiest road in Datang so far.

Both official and non-governmental will choose this path as their first choice.

Of course, there is another reason, that is, Tongguan, there is this checkpoint guarded, unless it is the nearby natives who will choose the mountain path, other people do not dare to take that kind of road at all, even if they go, it doesn't matter, many places can't even cross the carriage.

It is precisely because of this special geographical environment that Tongguan has created an important position in Chinese history, which is an important checkpoint linking Guanzhong and the Central Plains.

Li Shimin and Li Yuanjing glanced at each other, and immediately smiled.

Both of them understood the meaning in each other's eyes, and Li Shimin was not polite, and explained with relief: "Although Longyou Dao is important, it is not the most important so far, if I am not mistaken, you should have taken into account the potential threat of Tuyuhun, so I want to build this road first to prevent trouble!" ”

"Father is wise!" Li Chengqian felt that there was something wrong in his heart, and his thoughts were actually seen through by his father at a glance.

But what made him even more depressed was that his father didn't seem to support his decision.

"What you have considered, I have thought about as well, and if it weren't for the fact that the tide is constantly changing, I would have made the same decision as you. But now the situation is different, although the priority construction of the official road of Longyou Road has a certain help in military aspects, but it deviates from the current national policy of Datang. Li Shimin said slowly.

"National focus?" Li Chengqian was stunned for a moment, and then thought about it seriously, he is not stupid, can't he see what Datang is doing now? Puzzled: "Developing a business? ”

"To be exact, it should be economic development!" Li Shimin nodded, but still corrected some of Li Chengqian's mistakes.

Of course, Li Shimin has Li Shimin's considerations, Tuyuhun has become more and more disobedient in the past few years, although he is still respectful on the surface, but he always has one thing on the surface and one thing in secret.

In fact, this matter was originally settled after the destruction of the Turks, but the Tang Dynasty then focused on the sea to the east.

Although Datang is powerful, it can't fight on all sides, so the pressure on Tuyuhun's side will naturally be reduced.

Tuyuhun seemed to see the hope of rising, so he secretly wanted to move.

Although Datang did not give much military pressure to the other side, the secret reconnaissance was not small at all.

"I originally wanted to conquer Tuyuhun, but it happened to be a military reform, so I put it on hold for the time being, but this also gave Datang more time to prepare, and I wanted to conquer Tuyuhun in the ninth year of Zhenguan!" It was the first time that Li Shimin proposed this idea in front of others, which was something that even Fang Xuanling didn't know.

"What?" Li Chengqian was taken aback: "Father, there is still more than a year to go, will it be a little early?" ”

In the face of Li Chengqian's shock, Li Yuanjing calmed down a lot.

Indeed, it is indeed a bit early to consider Li Chengqian's identity.

After all, the current Datang is not the Tang Dynasty a few years earlier, with the bumper harvest for several consecutive years, the imperial court has enough food to fight.

If you really prepare, you can prepare it in three months at the earliest, which is not a big deal at all.

"As a monarch, you must not follow the rules, you must know how to make trade-offs according to the current situation, Datang's current national policy is to develop the economy and develop people's livelihood, so you must be extra cautious about going to war, even if you have to go to war, you must be fully prepared in advance, so as not to affect other aspects." Li Shimin said slowly.

In fact, he didn't plan to tell Li Chengqian about this, but since reading Li Yuanjing's letter, he decided that it was time for the prince to accept something new.

The trip to Jiaozhou exposed the fatal flaw of the prince's lack of actual combat experience, this problem has been common to princes in all dynasties, but the severity of the problem is just the severity of the problem.

Li Shimin naturally has a scale in his heart, he will balance himself, so that the prince will not affect his status while being exposed to more things, otherwise, Li Yuan, a living example, is in front of him.

"How is it possible that the war does not affect other aspects?" Li Chengqian looked up with difficulty and said, he really couldn't think of it.

"To a certain extent, war is actually conducive to economic development." Li Yuanjing said suddenly.

Li Shimin frowned slightly, war is conducive to economic development?

Funny, right?

If it had been placed in the past, once the war began, all kinds of things in the country would have almost fallen into semi-paralysis.

The reason why Li Shimin moved the time of the war was nothing more than to take into account the gradual reduction of the army's dependence on the civilian population after the military reform, and taking advantage of this extra-long period of war preparation, the materials needed by the army could be transported to the border in advance a little bit in advance.

In this way, when the war starts, the logistics baggage battalion only needs to transport supplies from the cantonment on the border to the front line.

In the past, it was often the localities that began to prepare after receiving orders, and then transported them directly to the front line, and by the time they arrived at the front line, the troops had long since lost sight of where they had hit.

The front-line troops, on the other hand, will start the war when there is a certain amount of material reserves, and will not start until all the supplies are in place.

This time, in order to avoid affecting the people, Li Shimin chose this method.

"Don't look at me like that, what I'm saying is the truth!" Li Yuanjing smiled slightly, and continued: "Before the military reform, the Tang Army did not have the ability to go to expeditions, although they could go to distant places to fight, but it was just a campaign, and they couldn't hold it at all.

But now it's different, the current Tang Army can both fight and garrison, and a long career in the military camp will allow them to alleviate the plot of loving their home to a certain extent, and everyone knows the five-year contract, so it's actually the same for them to go where they are stationed, anyway, they can't go home for five years.

And the biggest difference from the past is that in the past, if the army did not withdraw, they could not come back, not to mention ten or eight years, that is, they couldn't stand it for two or three years, but now it is different, whether the army is withdrawn or not, when the time is up, if they choose to retire, they can still go home, and at the same time there will be new people to supplement the past.

Therefore, when conquering the plateau such as Tuyuhun and Tubo or other distant places, it is recommended that the imperial court issue plateau or expeditionary subsidies to the troops, which does not require much, but this will definitely increase the motivation of the soldiers.

Of course, this money is not spent in vain, since I went, of course, I want to include it in the territory of Datang, otherwise why bother to go to war?

After the situation is stabilized, you can choose to build a city, gradually migrate the people over, and wait for a few decades, this place will completely become the territory of the Tang Dynasty.

And how can the materials needed to build a city be comparable to that of building roads? One or two cement workshops simply can't meet the demand, material resources and manpower, don't these cost money? Anyway, the imperial court is not short of money......"