In the case of Japan, that means supporting a move to amend the MacArthur-era constitution which makes it difficult to send the Self-Defense Forces abroad (including for the defense of Taiwan or South Korea) and a more recent political decree that caps military spending at 1 percent of GDP.
I think that Japan would be better served both to formally revise Article 9 and to increase its military budget from around $50 billion per year to more like $100 billion.
As to Mr. Boot's "The British tried confrontation with Germany (symbolized by the 1904 Anglo-French Entente Cordiale and an Anglo-German naval arms race) and appeasement with Japan (the 1902 Anglo-Japanese Alliance and considerable aid for the Imperial Japanese Navy until the late 1920s)", I am not so sure that "appeasement" is the word that I would have chosen since the British-Japanese relationship of the early 20th century seems to me to have been more solid than that.
Agreed. The Royal Navy wasn't "appeasing Japan". It was shoring up a threat to Russia and so maintaining the balance of the five powers.