Stories of the Japanese 00677 [Mid-Kamakura Period] Kublai's Intimidation

Kublai said to King Wonjong of Goryeo,
"You always say you will repay my kindness, but this is the opportunity to do so. Fulfill it quickly."
and ordered him once again to send an envoy to Japan.
Goryeo's senior vassal, Yi Jang-yong, had no choice but to decide to send Pan Bu as an envoy.
In January of the 5th year of Bun'ei (1268), Pan Bu crossed the sea and arrived at Dazaifu carrying Kublai's state letter. The person in charge of Dazaifu at the time was Shoni Sukeyoshi (1198–1281).
Originally, the head of Dazaifu was the "Dazai no Sotsu," and the deputy was the "Dazai no Gon no Sotsu." The second-in-command was called "Dazai no Suke," which was divided into two ranks: the senior rank was called "Dazai no Daini" and the junior rank was called "Dazai no Shoni." The family that had inherited the position of Dazai no Shoni for generations had come to use "Shoni" as their surname, taking it from the title of their office.
Shoni Sukeyoshi received Kublai's state letter from Pan Bu, but this letter also had a message from King Wonjong of Goryeo attached. The message from Wonjong was roughly as follows:
"The Emperor of Yuan wishes to establish relations with your country this time out of a desire to make Yuan a more honorable nation, and it seems there are no ulterior motives. If you send a reply from your country, I am sure that your goodwill will be rewarded. Why not send an envoy? However, everything is up to your country's discretion."
It seems Goryeo was trying to handle the matter as peacefully as possible. They likely hoped that if Japan sent a reply, even if just as a formality, they could avoid war.
This state letter arrived in Kamakura on the 8th day of the intercalary first month. It took quite a long time, but it seems that time had passed while they were arguing at Dazaifu over whether or not to accept it.
The shogunate must have received this state letter with great shock. The Regent Masamura was a 62-year-old man, and the co-signer Tokimune was a 16-year-old boy. I do not know what kind of discussions took place, but the shogunate's decision was
"We should not send a reply."
Indeed, at the end of the state letter, there was an intimidating phrase written:
"I do not wish to use military force. Think carefully."
They must have considered it rude.
Since the state letter was addressed to the "King of Japan," the shogunate decided to consult the Imperial Court as well, adding their opinion that it should be ignored.