The sea route running through the New World, from Fish-Man Island to Dressrosa.
This was something Tsugikuni Yoriichi had been planning all this time. The sea conditions in the latter half of the Grand Line were vastly different from those of the Four Blues. Here, sailing between islands was no easy task, and the existence of Log Poses also restricted the sea routes to a certain extent.
After operating in Dressrosa for so many years, Tsugikuni Yoriichi had finally come to recognize a reality: the pirates of the New World could never be killed off completely.
The natives of the New World were either lured and coerced by pirates, or had the desires in their hearts magnified, setting sail to gamble for a future. Moreover, the sea routes between the first and second halves of the Grand Line had not been cut off. All these factors meant that the number of pirates in the New World would not decrease, but increase instead.
The number of pirates Tsugikuni Yoriichi and his Dawn Branch could kill was probably not even as great as the number those pirates wore down through slaughtering one another.
To completely change this situation, Tsugikuni Yoriichi first wanted to block the routes between the two halves of the Grand Line.
Whether it was the World Government or the pirates, only by sealing off the sea routes could Tsugikuni Yoriichi settle down and slowly deal with the pirates of the New World, uprooting the "soil" that bred pirates.
Only by striking at pirates at their source could they possibly create a relatively harmonious world environment.
Moreover, the Marines led by Fleet Admiral Sengoku were currently making great strides in the Four Blues. To Tsugikuni Yoriichi, that was also a good thing.
If the cost of relocating a branch had