'China is watching': Election victory for Japan's PM could threaten stability of region

However you cut it, this is a one-woman story.

Sanae Takaichi has landed a mandate, a landslide so decisive that just a few months ago it would barely have been believed. And it could well change Japan and this region.

When she assumed the leadership of the ruling Liberal Democratic Party (LDP) in October, following the resignation of her unpopular predecessor, the government she inherited was floundering; losing seats, losing trust and struggling to recover from a financial scandal. In just four months, she's managed to turn this into a supermajority, winning more seats than her party ever has since it was founded in the 1950s.

Alongside her coalition partner, she now has the numbers to not only change the constitution but override any challenge from the consultative upper house of Japan's National Diet. It is, in essence, a carte blanche for her to see through her vision.

And see it through, she almost certainly will. Indeed, many people we spoke to here cited her straight talking, consistent and "get-it-done" approach as being one of her biggest attractions.

"I think Japan will get better and better," smiled one man enthusiastically at an LDP candidate's watch party. But Takaichi also comes with clear convictions about what it is she stands for and what she wants to achieve.

Indeed, behind the drum-playing, selfie-taking and motorbike-riding force that has undoubtedly livened up a normally pretty dry political scene, she has an ultra conservative vision and a resolutely nationalist outlook. Among the changes she is most likely to make are increasing Japan's defence spending and altering the constitution to explicitly recognise its armed forces.

Read more:Japan's China-provoking PM raises the stakesCan Japan's first female PM tighten her grip on power? This is controversial, as officially Japan is still a pacifist country whose forces are only meant to defend. But support for these changes seems remarkably broad, even among younger voters.

Indeed, at a gathering of students watching the results together in Tokyo, the idea that Japan should be more confident, even assertive, was clearly a motivating factor, a sense, perhaps, that post-war apologism is now somewhat outdated. "She used the catchphrase 'strong and prosperous Japan', and until now Japan's prime ministers had not taken such a clear stance on national defence.