The sweeping victory Japan's ruling coalition secured in the Lower House election on Sunday heralds a big change in Japan, for better or for worse.

The two coalition parties - the Liberal Democratic Party and Komeito - will chair all the committees in the more powerful chamber of Japan's parliament, they can even override decisions by the Upper House, and Shinzo Abe will be sworn in as prime minister for the third time.

The third Abe administration now has a free hand in all issues, be they social, economic, security or diplomatic.

And, an overt nationalist and historical revisionist, Abe has a big plan for Japan. He is eager to restore Japan's position as one of the leading countries in the world, worrying that its voice and influence are shrinking, and he is seeking a "departure from the postwar regime" to "bring back Japan". With four years ahead, his plan might seem to be within his grasp, but whether he can bring Japan back is open to question.

In an interview with the Economist before the election, Abe married his economic policy goals with his diplomacy. "We have to have a strong economy to have a strong diplomacy," he said. And it's his diplomatic moves that could have the greatest impact on Japan's future.

In the past two years he has pushed step by step toward his plan to depart from the postwar regime.

He has established a Japanese National Security Council. He announced the first National Security Strategy and the National Defense Program Guidelines that introduced the concept of "a Dynamic Joint Defense Force".

Abe's government has also reinterpreted the Constitution to allow the country to exercise the right of collective self-defense, and it has formally lifted Japan's decades-old ban on weapons exports. It has also revised textbook screening guidelines to give Japanese children a more patriotic take on modern Japanese history and to better reflect the government's view on territorial issues. During the election campaign, the controversial State Secrecy Law went into effect.

As former Japanese diplomat Ukeru Magosaki warned on Sunday, the country is tilting right fast.

Abe will likely push with fresh urgency next year a bid to have some of the legislation passed in the parliament to allow Japan's Self-Defense Forces to play a larger role in the region and world.

While a review of the Japan-US Defense Cooperation Guidelines will top his third premiership's agenda. The guidelines were supposed to be updated this month but were delayed by the snap election.

For Abe, a new Constitution is the issue closest to his heart. Japan's nationalists believe that the supreme law was imposed on Japan by the Allies in the aftermath of WWII.

In an interview with Asahi TV Sunday night, Abe said: "To amend the Constitution has been our party's long-cherished wish since its establishment. We will emphasize the need to amend the Constitution and make efforts to see growing public debate on the issue."

But this is not going down well with Japan's neighbors.

Japan has not shown enough historical reconciliation with its neighbors. And true to his rightist roots, Abe denies that "comfort women" were abducted and forced to provide sex to soldiers of the Imperial Japanese Army before and during WWII.

Abe will need to engage South Korean President Park Geun-hye as the 50th anniversary of the two countries' peace treaty looms in 2015. So far he has had no formal meeting with Park.

Aware that his agenda is creating waves that are rocking the boat of the postwar order, Abe will continue his globetrotting diplomacy under the slogan "proactive pacifism". He has visited 54 countries in two years, the most for a Japanese prime minister.

His most notable visit was probably to Beijing in November, where he met with Chinese President Xi Jinping, though briefly.

China and Japan reached an agreement on four principles, to pave the way for the talk between Xi and Abe. But once back in Japan, Abe and his Foreign Minister Fumio Kishida rushed to go back on the agreement, saying Japan has not changed its stance on territorial and history issues.

Plainly, China and Japan still have many high hurdles to overcome if they are to move their relationship onto a normal, if not friendly, track.

At home, Abe is now able to seek to do whatever he wants in the next four years - his last chance to govern Japan. His nationalism and historical revisionism, combined with his ambition to rearm Japan, will add to the uncertainty of the situation in East Asia. The world may also need to keep an eye on whether Abe's approach will further shake the foundations of the post-war order.

The author is China Daily's Tokyo bureau chief. caihong@chinadaily.com.cn