Sima Yi has already made a contract to Lü Bu, and in 220, the Suez Canal will be opened, and Lü Bu will be able to command the army westward into the European continent.

Lu Bu also increased investment in naval construction, striving to raise the strength of the navy to a higher level before 220.

Even the navy began to form a separate Mediterranean fleet, which would be supplemented by elite soldiers from the two oceanic fleets in preparation for the upcoming big war with the Roman Empire.

Lu Su had already arrived in Alexandria, where the Han and Persian empires had initially established a small combined fleet in the Mediterranean.

Protected by fortified coastal batteries, the shipyards of Alexandria had built four galleons of 500 tons, and the Persian Empire had built four galleons of the same design and tonnage.

Lu Su personally commanded this small fleet, including eight 500-ton Chang'an-class warships and eight 300-ton reconnaissance ships, which had repeatedly fought the Roman navy on the Mediterranean coast, especially in the eastern Mediterranean.

Medium and long-range artillery battles were a clear advantage for Lu Su, the new warships of the Romans had not yet been put into service in a large area, and the original oar-rowed warships did not have room for artillery, but if they relied on the help of broadside battles, the experienced Roman soldiers had a slight advantage.

In the Mediterranean, the monsoon winds at sea were weak, and there was no advantage for sailing ships, but the Roman triremes and four-rorees were more agile and maneuverable.

However, Lu Su was not too worried that the Han Navy would have many large warships in the Mediterranean Sea in the future, and the number of guns on them was very large, and I was afraid that it would not give the Romans a chance to take over the battle.

Moreover, the main task of the navy is to protect the land force to cross the strait smoothly and land on the European continent, and it does not necessarily have to be a duel with the Roman navy, and the cover task is more than enough for the warships of the Han navy.

Moreover, the Persian Empire is building a large number of oared warships in order to match the height of the Han Navy and complement each other's shortcomings.

They had occupied so many provinces along the Mediterranean coast that they had to build a navy to consolidate their rule.

In 219, it passed smoothly and nothing major happened.

Only in the direction of Yizhou, the Han Imperial Navy and the Wu Navy fought a medium-scale naval battle, because Wu provided protection for pirates along the southeast coast such as Ling Tong and blocked the bandit fleet of the Han Imperial Navy.

The two sides fought a naval battle off the coast of Huiji, which ended with the Han navy having a slight upper hand, and each side dispatched eight warships, all of which were 1,000-ton warships.

After a naval artillery bombardment, no one sank the other, but they were only beaten with holes, and many sailors were injured.

Wu Guo's watertight compartment technology learned from the Han Dynasty played a huge role, both sides used solid bullets to attack the opponent's waterline part and sink the opponent, but the good watertight compartment technology protected the warship that entered the water and could still float on the sea.

Wu paid attention to naval construction and initially achieved results, and their naval fleet had been able to conduct a preliminary confrontation with the Han navy, of course, the Han army was not worried.

First of all, Wu did not have the main warships of the Han Navy, which already had a giant ship of 3,000 tons, and Wu Guocai could only build a 1,000-ton warship.

Secondly, the naval guns of the Han army have begun to be updated, and even the shells used have begun to be replaced, which is also impossible for Wu to keep up with.

In any case, in order to monitor and control its opponents, the Han Empire stationed naval fleets with sufficient strength to monitor and guard them around the Wu State, including the Panyu Military Port in Nanhai County, the Wenchang Military Port in Zhuya County, and the Zhoushan Military Port at the mouth of the Yangtze River.

The number one imaginary enemy of the Pacific Fleet of the Han Navy is the navy of Wu, and the top priority of the intelligence department's large number of intelligence personnel in Wu is the intelligence of Wu's navy.

A large number of undercover agents have successfully broken into the high-level circles of the Wu army and navy, and have mastered a large amount of confidential information.

To put it mildly, the military of the State of Wu has no secrets in the eyes of the military of the Han Empire, and it is naked.

Wu himself was more or less aware of this embarrassing situation, so their focus was still on colonial development and the development of maritime trade.

Some of Cao Pi's practices and ideas could not be supported by Lu Xun and others, even Cao Zhen of the Cao clan also disagreed with Cao Pi's views, and he agreed with Lu Xun's development policy.

Both Lu Xun and Cao Zhen believed that since it was no longer possible for Wu to defeat the Han militarily, they should find another way to vigorously develop commerce and trade, and only with money could they expand their army and research new weapons.

They believed that Wu should learn from Liu Bei's Rinan Kingdom, give up the idea of fighting for hegemony, and concentrate on developing Nanyang, but there might be unexpected gains.

After Cao Pi grasped the power of Wu State, he was not at ease with some of the old ministers of Wu State, after all, they were the head snakes of the land, and they had been operating in Wu State for many years, and there were many henchmen.

Although they formed an alliance with Cao Pi, many of the imperial powers were still in their hands, and Cao Pi and the former ministers of Wei could not do whatever they wanted.

Cao Pi tried every possible way to slander Zhang Zhao, Gu Yong and others for wanting to re-establish the old lord Sun Deng and replace Cao Pi by means of framing him.

The exchange of forged letters and a forged covenant gave Cao Pi a sufficient excuse to arrest Zhang Zhao and others, and Lu Xun maintained neutrality on the premise that he would not touch anyone in the military.

In the end, Zhang Zhao, Gu Yong and other 23 veterans and important ministers of Wu were beheaded by Cao Pi for the crime of rebellion, and the three clans were exterminated, which caused a sensation in the entire Wu State and shook the whole country.

No one in the court objected to Cao Pi, and many of the ministers were newly promoted newcomers by Cao Pi, and Cao Pi took back the power in the hands of many Zhang Zhao and others.

Although Cao Pi kept his promise and did not move any of the military, when recruiting new troops and establishing a new army, the officers appointed were all members of the Cao clan or former ministers of the Wei state.

Cao Pi's henchmen gradually broke into the military of Wu State, and the army was no longer monolithic, and Lu Xun could not stop this, after all, the source of funds for the army was in the hands of Cao Pi and his party.

Cao Pi was familiar with these ways in the court, and by doing some addition and subtraction, he could gradually weaken the influence of Lu Xun and others, and completely grasp the military and political power of Wu.

Moreover, Cao Pi also sent people to sneak into the mainland quietly, instigating and recruiting the old Wei and the people of Wei, and smuggling them from the southeast coast to Yizhou Island.

Over time, the proportion of the population of Wu has also changed greatly, and Cao Pi pacified and educated the indigenous people of Yizhou Island, rather than blindly purging them.

Teaching them advanced Han culture and farming techniques improved their quality of life, influenced their beliefs, and quickly integrated into the Wu Han society.