TOKYO (Reuters) - Voters in Japan are deeply divided over Prime Minister Shinzo Abe's campaign to revise its 70-year-old pacifist constitution, according to a poll released on Wednesday, against a backdrop of growing tension in the region, particularly over North Korea.
The Nikkei Inc/TV Tokyo survey, published on the anniversary of the constitution's enactment, showed support growing for Abe's push to revise a charter written by the United States after Japan's defeat in World War Two and never amended.
About 46 percent of respondents favored keeping the constitution as it is, four percentage points lower than a similar poll last year.
The number favoring a change stood at 45 percent, up five percentage points from a year ago.
Nuclear-armed North Korea has over the past year stepped up missile tests, the most recent of which was a failed launch on Saturday.
It has also threatened to attack Japan.
North Korea accused the United States on Tuesday of pushing the Korean peninsula to the brink of nuclear war after a pair of strategic U.S. bombers flew training drills with the South Korean and Japanese air forces.
Under the constitution's Article Nine, Japan forever renounced its right to wage war, leaving it open to interpretation whether it should maintain forces and how they could be used.
Successive governments have interpreted the constitution as allowing a military for "self-defense" only, and Japanese troops have taken part in international peace-keeping operations, as well as a non-combat reconstruction mission in Iraq during 2004-2006.
Abe, in a video message to a gathering celebrating the charter's anniversary, proposed making explicit reference to the existence of the Self-Defense Forces (SDF) in the constitution, Kyodo News reported. The document currently does not make any mention of the SDF.
"By making explicit the status of the SDF in the constitution during our generation's lifetime, we should leave no room for contending that (the SDF) may be unconstitutional," Abe said.
Under Abe's watch, parliament in 2015 voted into law a defense policy shift that could let troops fight overseas for the first time since 1945, but any constitutional revision would require the backing of two-thirds of members of both houses of parliament and a majority of voters in a referendum.
In March, Abe's Liberal Democrat ruling party formally proposed that the government consider acquiring the capability to strike enemy bases and beef up missile defense in the face of the North Korean threat.
Acquiring such weapons would likely anger China, where bitter memories of Japan's wartime aggression run deep.
A separate survey released by Kyodo News on Saturday showed 49 percent of respondents said Article Nine needed to be revised, against 47 percent opposing a change.
(Reporting by Tokyo bureau; Editing by Simon Cameron-Moore)