It is fairly easy to assess the relationship between Shinzo Abe’s Japan and Xi Jinping’s China. Neither likes the other very much. Both are using nationalism as a prop to further policy aims. Both conceivably find it useful to have a “tough man” on the other side, the better to push against.

Less easy to calibrate is the state of relations between Japan and the US. This ought to be far easier to decipher. Japan is, after all, the US’s most important ally in Asia, the “unsinkable aircraft carrier” that has hosted US fighter aircraft and troops since the end of the second world war. Now, in Mr Abe, it has a leader who, after decades of American prodding, is finally willing to adopt a more robust defence posture and revisit the “freeloader” defence doctrine that pacifist Japan has long embraced. Yet having attained what it has long been after, Washington is showing signs it is getting cold feet.

One sign of that was its expression of “disappointment” after the December visit of Mr Abe to Yasukuni shrine, which is regarded as a symbol of Japan’s unrepentant militarism by China and South Korea. In the past, Washington has privately voiced its displeasure at Yasukuni visits, but has not publicly reprimanded Japan. Tokyo was taken aback by the use of the word “disappointed” – translated as shitsubo – which sounds harsh in Japanese.