As a vice-minister in the finance ministry (MoF), he has been the choice of several prime ministers in sorting out tricky trade negotiations. His cogitations on postmodernism have been published in journals, and among currency traders he earned the nickname Mr Yen for his ability to move the markets with a carefully deployed remark.
But he finds himself in hot water - not over the economy, or corruption scandals, but over Japan's constitution.
Drafted in 1945 by the US occupying forces led by Douglas MacArthur, it is showing its age. Article Nine, the "peace" clause, vows that "land, sea and air forces, as well as other war potential, will never be maintained."
But in the the "Self-Defence Forces" Japan possesses one of the largest military machines in the world. Every year, on Constitution Day, newspapers compete to produce proposed revisions.
Left-wingers insist Article Nine be followed to the letter; right-wingers demand its abolition. This month Mr Sakakibara, famed for his outspokenness, pitched in. And then the trouble started.
"It should be completely redone," he told Chuo Koronin magazine an interview published yesterday. "The constitution should be a document which resiliently changes with the time, and when you look at politics and the way the government works, the constitution has to change or there'll be something wrong.
"The legislative body (of government) has fundamentally lost its will to hammer out legislation. What it should be doing is rewriting the constitution."
On the face of it, this all seems reasonable enough, but the reaction has been swift and cold. Members of the Social Democratic Party, guardians of the peace clause and members of the ruling coalition, denounced Mr Sakakibara for "superseding the bounds of his brief". The party's leader, Takako Doi, whom Japanese call their "Iron Lady", has said it will summon him for a dressing-down. Mr Sakakibara has been more outspoken than the average bureaucrat, though no one minded this when it tweaked the markets in the right direction.
But the timing of the remarks is sensitive for two reasons. One is the scandal embroiling the MoF, a tale of corruption and collusion between banks and their supposed watchdogs, and of bureaucrats selling favours for expensive meals in restaurants where the waitresses wear no knickers.
The MoF's reputation has never been lower, and this is not a time for its spokesmen to get uppity.
The second reason is the timing, a few days in advance of an anticipated second Gulf war.
The constitution's biggest test came in 1991, after the invasion of Kuwait, when Japanese politicians agonised for weeks over whether to send troops to the Gulf and ended up just sending a big cheque.
When the US ambassador to the United Nations, Bill Richardson, came to Tokyo seeking support against President Saddam Hussein, the response, in traditional Japanese style, was measured, vague and indecisive.
Everything, in other words, that Mr Sakakibara is not.Reuse content