Japan's next prime minister is a career dissenter, but experts doubt he can govern as one

Shigeru Ishiba, the man set to become the next leader of Japan, has made a career as a political outsider and opponent of party orthodoxy. However, some experts doubt that the former defense minister will manage to govern as such.

The seasoned politician who won his fifth bid to become the head of the Liberal Democratic Party on Friday has long been a critic of former Prime Minister Shinzo Abe and his legacy of "Abenomics" commonly defined by loose monetary policy, fiscal stimulus and structural economic reforms such as tax cuts. 

Ishiba, on the other hand, has shown support for increasing taxes and fiscal tightening while also having opposed the Bank of Japan's long-held policy of negative interest rates that started under Abe.

"The legacy of Shinzo Abe is still enormous, and how to engage with that legacy and whether it's time to course correct became a defining question in the LDP race," said Tobias Harris, founder and principal of Japan Foresight.

The election ultimately came down to a runoff in which Ishiba defeated economic security minister Sanae Takaichi, who presented herself as the more Abenomics-aligned candidate. Japan's parliament is expected to formally vote Ishiba into the role Tuesday.

"Based on what he's said in the past, he appears to be a leader with a new mindset and vision for the country," said Sayuri Shirai, professor at Keio University and a former BOJ board member, adding that Ishiba and Takaichi had represented very different wings of the party.

But the economist said there's still a lot of uncertainty about whether Ishiba can actually follow through with some of the outsider policies and philosophies that have defined his political career. 

In a press conference soon after his victory, Ishiba