The election to Japan's upper house on Sunday has acquired added significance because the result would be critical to the ruling Liberal Democratic Party's attempts to amend the country's pacifist Constitution.

Constitutional amendment, the amendment to Article 9 in particular, has been a controversial issue in Japan since the end of World War II. Article 9 renounces war, and notes that the prohibition on the use of force by Japan is a clear constitutional rule that the Japanese government has to follow. It also prohibits the maintenance of armed forces and denies Japan the right of "belligerency".

And it is precisely to change Article 9-which would allow Japan to have a regular military and become a normal country-that Japanese Prime Minister Shinzo Abe has made constitutional amendment his goal.

But Abe should realize that amending the Constitution is no small feat because for that, the ruling coalition of the LDP and Komeito has to have a two-thirds majority in both houses of parliament, and then win an absolute majority of votes in a referendum. Several attempts have been made to amend the Constitution, but none has been successful.

Abe should also know that the ruling LDP's coalition partner Komeito is a conservative party which is skeptical about amending Article 9.

Differences among political parties, even within one party, have made it almost impossible for the LDP to amend the Constitution.

For example, there are diverse voices on constitutional amendment within the Abe-led LDP. While some support revising the pacifist Constitution to allow Japan to have a regular military, others say the Japan Self-Defense Forces, which has constitutional sanction, should be strengthened to the level of a full-fledged military.

The LDP and Nippon Ishin no Kai are in favor of a constitutional amendment. But the Constitutional Democratic Party of Japan, Democratic Party for the People, and the Japanese Communist Party strongly oppose the idea.

While the LDP has maintained its lead in the polls for the upper house election and asserts that the Constitution should be revised, Komeito remains skeptical about any amendment to Article 9, making it uncertain for the coalition to win two-thirds seats in the upper house and proceed to amend the Constitution.

According to Asahi Shimbun's annual survey ahead of Constitution Day on May 3, doubts over constitutional revision have increased.

On the one hand, a large majority of the respondents said they don't see any upsurge in the call for constitutional amendment despite Abe's desperate efforts.

On the other hand, when asked if Article 9 should be amended, 64 percent of the respondents said "no", up from 63 percent last year, while only 28 percent said "yes", down from 32 percent last year.

And Yomiuri Shimbun's nationwide opinion poll in July showed people are more concerned about "social security matters" such as pensions than constitutional amendment. In fact, 37 percent of the respondents, the biggest group, said they vote for the party which promises to provide the best possible social security for citizens, with only 7 percent saying constitutional amendment is the most important issue for them.

Moreover, apart from heeding the call of a majority of Japanese citizens, Abe and the LDP should also take into consideration the opinions of Japan's neighbors such as China, the Republic of Korean and the Democratic People's Republic of Korea, where the invading Japanese troops committed many atrocities before and during World War II, before venturing to amend the Constitution.

If the LDP tries to amend the pacifist Constitution without resolving the historical issues with the neighboring countries and without understanding the true sentiments of Japanese citizens, it will face opposition from the Japanese people as well as the international community.

The author is head of the Institute of International Politics at and deputy director of Northeast Asia Research Center, Jilin University. The views don't necessarily reflect those of China Daily.