The hardline stance of Japan is half due to the militaristic obsession of the post-WWII Japanese political establishment that was not thoroughly cleansed, and the other half is internal propaganda. The base of Haruna Kawakita is extreme right-wing, so she definitely needs to cater to them.
This incident also illustrates one thing: internationally, if you have strong military power but don't use it, you will indeed be seen as a paper tiger.
Japan is a country that fears strength but does not cherish kindness. If you beat it into submission, it will kneel down and call you father.
Historically, take the Tang Dynasty as an example (the Battle of Baekgang), and also the Tokyo firebombing by LeMay.
Original text: www.toutiao.com/article/1848824816151560/
Statement: This article represents the views of the author himself.