TOKYO -- Within the space of three days, Japan's three biggest political parties have shattered the 47-year taboo on any hint of change in this country's U.S.-written pacifist constitution.
Senior officers of the governing Liberal Democratic Party and the opposition Social Democratic and Komeito (Clean Government) parties all have called for what two of them separately described as "a great debate" on Article 9 of the 1946 constitution.
That article "forever renounces" war as a means of settling international issues and prohibits maintenance of an army, navy or air force equipped for any but self-defense fighting.
"For Japan, even open debate of Article 9 is a watershed equivalent to the fall of the Berlin Wall in Germany, because it defines the end of Japan the defeated World War II power and pliant postwar American protege," a European embassy political analyst said.
"It's too soon to guess whether the country will try to reinvent itself or merely throw off a skin that's grown too tight, but Japan the independent post-Cold War actor is going to be substantially different from the Japan we've known up to now."
Wednesday, the Liberal Democrats' internal governing body tentatively agreed to propose the creation of a multiparty panel to review the constitution.
That forced the two main opposition parties to confront the issue directly or risk being left out of one of the biggest decisions the country has faced since World War II.
"Japan's position in international society is changing, and the Cold War is over," said Komeito's secretary-general, Yuichi Ichikawa. "It no longer makes sense to think of discussing Article 9 as something that is taboo."
Sadao Yamahana, newly elected chairman of the Social Democrats, said he didn't think a multiparty panel was needed but agreed that it was time to "discuss the issue in the Diet," Japan's parliament.
By week's end, both the Social Democrats and the Komeito had assigned internal bodies to take up the question.
Such talks seemed politically inconceivable as recently as last summer.
But Japan has been in deepening self-examination since last fall, when yet another money-and-politics scandal brought down yet another top kingmaker, Shin Kanemaru. Mr. Kanemaru's faction, the biggest within the Liberal Democrats, has since split in two.
His chief protege now co-heads a breakaway faction that styles itself as a spearhead for long-sought reform of a deeply corrupt political system. The protege, Ichiro Ozawa, also is a leading spokesman for reexamining Article 9.
Many Japanese also feel that a new Democratic administration in Washington requires Tokyo to take a more assertive role. For 12 years, most officials here have felt secure with Republican presidents who have been at least rhetorically committed to free trade and close relations with Japan.
The Foreign Ministry opened the new year with its official spokesman confirming that Japanese diplomats had decided to do less of waiting for leads from Washington and more of defining Japan's interests and having their country take initiatives.
For many Japanese, Article 9 inevitably is the symbolic core of any self-examination.
On one side, millions of leftists and additional millions of older, ordinary Japanese remember the arrogance and brutality of the Imperial Army of World War II years. Their fear of any restoration of political legitimacy to the military has been a powerful force sustaining the taboo.
On the other side, millions of nationalists and additional millions of younger, ordinary Japanese feel humiliated that their country cannot join international work such as the Somalia relief effort solely because it involves use of force overseas.
A law passed amid bitter legislative battles last year authorized the use of Japanese troops in United Nations peacekeeping operations so long as there was no danger of having to fight. Japanese troops promptly joined the U.N. operation policing the peace in war-ravaged Cambodia.
Within the ruling party, a growing body of conservatives and nationalists has worked for more than a year to create a chance to rewrite Article 9. But powerful LDP voices can be expected to speak against change.
Prime Minister Kiichi Miyazawa, who was on a tour of Southeast Asia when his party decided to join the debate, has spoken repeatedly of the "efficacy" of Japan's pacifist constitution in reassuring its neighbors.