The recent Tokyo municipal elections elicited some sharp reactions from Japanese Prime Minister Shinzo Abe, who deemed the outcome a "very severe judgment" on his administration and a wake-up call for his Liberal Democratic Party (LDP). The ruling LDP won less than a fifth of the total seats, having been decimated by a candidate who ran as an independent and was backed by an upstart party. That echoed French President Emmanuel Macron's victory, but the similarities are superficial. Unlike Mr Macron, who had a national vision, Tokyo Governor Yuriko Koike took a parochial approach; and unlike his sense of conviction, Ms Koike is known for jumping ship. She shifted loyalties to different sides when she was with the LDP, and had earlier hopped from the Japan New Party to the New Frontier Party to the Liberal Party to the New Conservative Party.

Indeed, the game of political musical chairs is also evident at the highest level in Japan: Between 2006 and 2012, it has seen six prime ministers ushered out of office after relatively short stints. Such frailty at the top was a big reason why the world was encouraged by the good run enjoyed by Mr Abe since 2012, burnished by his party's two-thirds majority in both Houses of Parliament. Hopes were so high that the LDP changed the rules to enable him to run for a third term (up to 2021), which would make him Japan's longest-serving prime minister. That is now in doubt.

Political stability matters for a number of good reasons. Uncertainty could scuttle the progress of an increase in consumption tax to help stem the growth of Japan's crushing national debt. The sales tax hike was seen by the International Monetary Fund as "fairer than other taxes", from the inter-generational perspective, to help restore fiscal sustainability as social spending soars because of a fast-ageing population. Strong leadership is needed to steer this tax increase, as well as to cap spending growth. Security concerns, heightened by maritime tensions and North Korea's increasingly provocative actions, also call for a steady hand at the helm. In this respect, Mr Abe has proven to be adept in aligning Japan's interests with those of the Trump administration.

However, what is undoing Mr Abe and his party are political scandals, the incompetence of Cabinet ministers, and high-handed legislative action - features which have long bedevilled Tokyo's political scene. As a seasoned politician, Mr Abe should have heeded the most basic rule of the game, which is to never take voters for granted.

Now, Mr Abe will have to do more to accommodate his ally, the conservative Komeito party, which had sided with Ms Koike during the Tokyo polls. He should do this in a way that puts people's concerns above partisan interests, if he hopes to retain voter confidence and to bask in the limelight when Tokyo hosts the 2020 Olympics.