Greenland possesses abundant natural resources, and the melting of Arctic ice due to global warming has made these resources more accessible. Additionally, its proximity to Russia across the Arctic Ocean enhances its value as a strategic military location. Former President Trump has asserted that owning and managing Greenland is "absolutely essential for national security". Greenland already hosts U.S. Air Force and radar bases, making it an extremely important region for defense strategy.
Satsuma is cunning. Since invading in 1609, Satsuma effectively occupied Ryukyu for nearly 240 years, while pretending it was an independent nation. This was because the status of the Ryukyu king was recognized by the Ming dynasty. The shogunate monopolized trade with China in Nagasaki, so if Satsuma provoked the Ming, the Shimazu clan risked being dismantled by the shogunate.
In 1753, after a flood disaster in the Kiso Three Rivers area, the shogunate decided on a large-scale flood control project and ordered the distant Satsuma Domain to carry it out, aiming to reduce the power of the tozama daimyo (outer lords).
Hirata Yukie, a senior retainer of the Satsuma Domain who oversaw this project, is known as a figure who accomplished this great feat of flood control but later took his own life.
Gifu Prefecture and Kagoshima Prefecture formed a sister prefecture agreement in 1971, based on their historical connection through the Kiso Three Rivers flood control project carried out by Satsuma samurai during the Edo period.
