As of late Prime Minister Fumio Kishida has had to cope with an unflattering nickname: "zōzei-megane," or “the four-eyed tax-hiker.”

But why?

Kishida hasn’t actually raised taxes for the public at large since he took office over two years ago — at least, not yet.

In fact, earlier this month his Cabinet approved a plan to cut taxes. Overcoming strong resistance from senior members of his Liberal Democratic Party, Kishida pushed ahead with a plan to cut ¥40,000 ($270) a year in income and residential taxes.

And Kishida, though now bespectacled, hasn’t always been associated with glasses, making the nickname stand out more.

During his tenure as foreign minister, Kishida, who was first elected to parliament 30 years ago, won the “Japan Best Dressed Eyes Awards,” but it wasn’t until about a decade ago that he began to regularly wear glasses in public.

Previous prime ministers have had their share of nicknames, too: maverick Junichiro Koizumi was once dubbed the "henjin," or weirdo, while Yukio Hatoyama was referred to as the “alien” and “loopy.”

While the use of such monikers didn’t stick with the public at large, the use of “four-eyed tax-hiker” seems more widespread. The derogatory nickname first gained traction on social media in the summer, but a few weeks ago it made its debut during a parliamentary committee session and in a news conference.

Commentators say the nickname might stem from Kishida’s own nebulous political ideology and unassuming persona.

“Nicknames express one’s character,” said Takuma Oohamazaki, a political analyst and CEO of election consulting firm J.A.G Japan. But in the absence of other defining characteristics, the nickname has been able to stick to Kishida, he said.

Since taking office, the prime minister has made bold promises to address some of Japan’s most daunting challenges — from defense to the falling birthrate — without articulating how he intends to foot the bill.

This lack of clarity has prompted widespread worries that a tax hike is on the horizon.

“It’s as if there’s a cloud of anxiety that he will raise taxes at some point, so of course he’s going to be called ‘zōzei-megane,'” Oohamazaki added.

“His message isn’t clear. For example, if hypothetically he has decided to (raise taxes) in two years, then he should say that. Or if he doesn’t intend to, he should just say so. Instead, he says that he’s ‘considering,’ and that comes across as weak.”

Take defense spending. In order to finance an ambitious plan to bolster Japan’s defense capabilities by doubling funding — to the tune of ¥43 trillion until 2027 — last December the government greenlit a plan to raise corporate, tobacco and income taxes by ¥1 trillion. But crucially, Kishida kicked the can down the road on any meaningful discussion about the timing of the tax hike, until 2025.

Additionally, pledges to earmark an extra ¥3.5 trillion for child care measures — part of an audacious plan to reverse Japan’s languishing birthrate — haven't been backed by a detailed funding plan.

Earlier this month, the Children and Family Agency presented a rough outline of a new funding plan, emphasizing the importance of a full review of government expenditure, but did not rule out a hike in insurance premiums.

On both fronts, Kishida has consistently avoided any mention of a potential increase to the tax burden, out of fear of hurting his already foundering popularity. Instead, he has painstakingly reiterated his pledge to return the fruits of increased tax revenue generated by a positive economic cycle to voters.

According to a column in the December issue of the monthly magazine Bungei Shunju, after zōzei-megane posts began to surge on the social media platform X in late August, one day Kishida blurted out, "I don't even remember saying anything about a tax hike, though," and then worked to dispel the image of being someone who hikes taxes.

This ambiguity around whether he will raise taxes, coupled with a rather colorless leadership style, has exacerbated disaffection with the prime minister, despite a certain level of public support for his signature policies.

That could have severe consequences for an administration that, just a few months ago, seemed on track to becoming one of the longest in Japan’s recent history.

“Kishida has had two years and he has shown no speed in decision-making,” Oohamazaki said. “During this period, citizens had a lot of time to think.”

With the debate on fiscal policy yet to reach its peak and the LDP entering its usual year-end debates this month, the zōzei-megane label might hang over Kishida for a while.