TOKYO (THE YOMIURI SHIMBUN/ASIA NEWS NETWORK) - Japanese Prime Minister Shinzo Abe won the ruling Liberal Democratic Party's (LDP) leadership election on Sept 20, securing a third consecutive term as the party head.

The victory has put him on track to becoming Japan's longest-serving prime minister.

Among 807 valid votes out of 810 from LDP parliamentarians and rank-and-file members, Abe won 553 votes to rival Shigeru Ishiba's better-than-expected 254.

With three more years in office, Abe will have many challenges to deal with.

US President Donald Trump congratulated his "good friend" Abe in a tweet, saying he looks forward to many more years of working together. Abe tweeted that he had "frank and constructive" discussions with Trump in a "truly relaxed atmosphere" in New York on Sept 24.

Despite the close personal relationship between the two leaders, Trump has been pressuring Abe to narrow Japan's US$69 billion (S$95.32 billion)trade surplus with the US and wants a bilateral trade agreement to address it.

Tokyo opposes a two-way deal for fear it would boost pressure on traditionally sensitive sectors, such as agriculture.

The Trump administration is also exploring raising tariffs on Japanese auto exports, a step Japanese say would do serious damage to the two economies and world trade.

At an economic forum in Vladivostok, Russia, on Sept 12, Russian President Vladimir Putin proposed that he and Abe sign a peace treaty, with no conditions attached, by the end of the year.

Tokyo has effectively ignored Putin's sudden proposal because of Japan's stance that a row over four small islands off Hokkaido - which were seized by the Soviet Union in the final days of World War II - must be settled before a peace treaty can be signed to formally end hostilities between their countries.

Amid international efforts to denuclearise the Democratic People's Republic of Korea, Abe is eager to meet with DPRK leader Kim Jong Un to resolve their disputes, including the decades-old issue of Japanese citizens abducted by the DPRK.

He also needs to work harder to push forward the improving China-Japan relationship.

During his new three-year term, Abe said he aims to pave the way to end deflation.

"Whether lucky or smart, Abe has overseen a strong period for the benchmark Nikkei Stock Average, which has more than doubled since he came into office in 2012," the Nikkei Shimbun said.

A weaker yen accompanied the Bank of Japan's bold monetary easing, boosting Japanese exports and inbound tourism.

Economic growth averaged a modest 1.3 per cent between 2012 and 2017.

"The biggest goal of our macroeconomic policy has been fulfilled as a result of measures taken by the government and the Bank of Japan to achieve 2 per cent inflation," Abe said, signaling he was no longer insisting on hitting the elusive inflation target.

After years of heavy money printing, the Bank of Japan has little ammunition left.

Japan's huge public debt and rising social welfare costs for a fast-aging population also leave Abe with little room to increase fiscal spending.

He has said he will implement a planned rise in the consumption tax from 8 per cent to 10 per cent in October 2019, but that could hit the economy just as Trump's protectionist policies could hurt Japanese exports.

The decisive victory on Sept 20 may embolden Abe to pursue his long-sought amendment to Japan's pacifist Constitution, although the hurdles remain high and doing so would carry political risks.

"It's time to tackle a constitutional revision," Abe said in a victory speech.

"Let's work together to make a new Japan," he added.

Constitutional revision is a decades-old pledge of the LDP since its foundation in 1955 and a goal that none of Abe's predecessors have been able to achieve.

Abe and his party want to rush a revision while their ruling coalition still holds a two-thirds supermajority in both houses.

The next upper house election is due summer 2019.

Abe seeks to submit a draft constitutional revision to an extraordinary parliamentary session this autumn.

He is proposing to add a clause to the war-renouncing Article 9, which bans the use of force in settling international disputes, to explicitly permit the existence of Japan's military, the Self-Defense Forces.

But Komeito, the LDP's junior coalition partner, is trying to put the brakes on Abe's push for constitutional revision.

Soka Gakkai, the lay Buddhist organisation that serves as Komeito's support base, is strongly opposed to Abe's plan.

Fifty-five per cent of the votes Abe secured came from rank-and-file members, a number believed to more closely reflect public opinion.

Some LDP seniors said the numbers will not bode well for the party in the next upper house election.

Ordinary LDP members are dissatisfied because economic recovery is not reaching their regional areas.

Many feel the Abe administration's economic policy mix only benefits major corporations and big cities, with local communities being cast aside.

Pundits say Abe is rushing his constitutional amendment plan to avoid any possible setbacks from the upper house election.

Abe has survived a series of scandals.

Despite attacks from opposition parties and criticism in the media, he has seen his support ratings bounce back to about 40 per cent, considered high for a Japanese leader after nearly six years in office.

But people's trust in Abe as a political leader has not improved because of his tough political style.

Abe is lucky that Japan's opposition imploded and has been unable to put itself together.

Also, two events - the imperial succession in 2019 and the Tokyo Olympics in 2020 - call for national unity.

The final term in office is supposed to be the time for legacy.

And rewriting Japan's Constitution may be the mark Abe wants to leave.

But constitutional revision is divisive. If a revision is rejected in a national referendum, Abe would likely have to step down.

Abe's third term means stability and continuity in Japan, which may encourage high-handedness in his administration.

The author is China Daily's bureau chief in Tokyo. China Daily is a member of The Straits Times media partner Asia News Network, an alliance of 23 news media organisations.