It was a crucial speech and as Taro Aso, the Japanese Prime Minister, stood up in parliament he was determined to get it right. Reading from a carefully worded document he proclaimed that his Government, like those before it, offered its sincere apology and remorse for the cruelties of the Second World War.

Between the writing on the page and the words which came out of the Prime Minister’s mouth, however, something went terribly wrong. Mr Aso had intended to say that he would follow (toushu in Japanese) the established statement of official apology. Instead, he mispronounced the word as fushu — meaning the stink of decay. “I support apology for the war” came out as something close to “I stench apology for the war”. It did not end there.

In the four months since he became Prime Minister Mr Aso has become notorious for the Japanese equivalent of George Bush’s bloopers. He has spoken of his hopes for “cumbersome meetings” with the Chinese Government, instead of “frequent meetings”. He has mangled the word “sluggish” into “slaggish”. His malapropisms have spurred a publishing boom, as hundreds of thousands of Japanese strive to avoid the same humiliating mistakes.

The Asoisms derive from the Japanese tongue’s unique way of using kanji — the Japanese characters that form the basis of the written language. In Chinese each character has a fixed pronunciation, but in Japanese the same character can be read in as many as nine different ways, depending on how it is combined with other kanji to form words.

Children, and foreign students of Japanese, often work out these pronun- ciations with the help of a phonetic syllabary. Adults, and certainly prime ministers, are expected to be able to know how each kanji should be read in a particular compound.

Most mistakes are at worst inconvenient, but some can be disastrous. The mother of all bloopers was perpetrated by a television announcer. Pointing to a sober graph of population changes, the woman referred to the “baby-boomer generation” (dankai no sedai) as dankon no sedai — the penis generation.

As a result of Mr Aso’s ideographic inadequacies, Japan’s publishers are enjoying a kanji boom, with books about the written language soaring up the bestseller lists. One title, Commonly Misread Kanji that You Think You Can Read but Can’t, has gone into its fifteenth edition and sold 600,000 copies in three months, bucking an overall slump in book sales.

Although it has no connection with Mr Aso, bookshops report that customers often ask for it as “the Prime Minister’s book”. Last month a member of the Opposition stood up in parliament brandishing a white board of tricky kanji to test the Prime Minister on the spot — he declined the challenge — and parents report that the name Taro has become a schoolboy’s taunt for a playground dunce.

No leader needs this kind of ribaldry but Mr Aso can afford it less than most. Since coming to power last September his approval rating has shrivelled from more than 80 per cent to below 20 per cent. Several key members of his Liberal Democratic Party are talking of rebellion.

It is assumed by many that he will go down in history as the leader who presided over the electoral defeat, and probably the destruction, of the LDP after 53 years of almost uninterrupted power.

This is partly a result of misfortunes beyond Mr Aso’s control such as the global economic crisis, which is hitting Japanese manufacturing, including household names such as Sony and Toyota, far harder than expected. Yesterday the electronics giant Panasonic announced that it is to close 27 factories and sack 15,000 workers across the world, half in Japan.

It also stems from Mr Aso’s failure to grasp the tenor of the times, and his high-handed bumptiousness when many Japanese are feeling humbled and insecure. The expression for this is KY or kuuki yomenai — “can’t read the situation”. In Mr Aso’s case it has taken on a second meaning “kanji yomenai”, or “can’t read kanji”.

Kanji mistakes that could get you into trouble

Date-otoko (dandy) mispronounced as itachi-otoko (weasel man). As in, "Section Chief Suzuki, may I say that you look quite the man weasel in that bow tie!"

Chinju (exotic animal) for chincho (esteemed, appreciated). "Caviar is an exotic Russian animal."

Dankon no sedai (penis generation) for Dankai no sedai (baby boomer generation). "Bill Clinton is an outstanding member of the penis generation."

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