TOKYO, May 20 - It seemed such a simple idea at first: the Government would build a history museum to mark the 50th anniversary of the end of World War II.

But the plan has set off a battle of its own. While everyone approves of a war museum in principle, the project has been delayed and shaken by bitter disputes about what it should exhibit.

"As the plans became more concrete, it became difficult to find a consensus," said Toshiaki Nagato, an official in the Ministry of Health and Welfare, which is in charge of the project. "So now we've decided that the exhibits will focus on daily things-boots and clothes and so on -that are really within the sphere of our ministry's work."

The battle over the museum in Tokyo bears an uncanny resemblance to the recent debate in the United States over the Smithsonian Institution's planned exhibit on the atomic bombing of Hiroshima.

In Japan, as well, the ambitious plans for the history museum are being scaled back. It will have a terrific collection of wartime boots but not much context beyond socks and shoelaces. The problem is that the history of World War II is less about Japanese soldiers' footwear than about whom they stepped on.

"I don't agree with this approach," said Chihiro Hosoya, a history professor who resigned from the commission that is advising the Government about the museum. "The exhibition must reflect the road to the Pacific War, so that young people can understand it."

Mr. Hosoya said he resigned when he concluded that the Government was trying to use the museum to justify Japan's entry into the war. For example, he said, the Government planned a display suggesting that economic forces in the 1930's compelled Japan to start the war.

This is a standard argument of those Japanese who refuse to apologize for the war. They say American economic sanctions and unreasonable demands left Japan little choice but to engage in all-out war. The argument has not been accepted by mainstream historians, nor is it well received by the countries where people were massacred during Japanese rule. In China, 10 million people-the Chinese Government says 35 million-died as a result of the Japanese invasion.

The museum is now not due to open until at least 1997, so it is too early to know exactly how the exhibitions will be prepared. But Mr. Nagato acknowledged that the Government had dropped a plan for an exhibition about the Nanjing Massacre, in which Japanese troops killed tens of thousands of civilians-or by Chinese count, 300,000-at the end of 1937 and beginning of 1938.

Critics also note that the museum will be on land next to the Yasukuni Shrine, an epicenter of Japanese militarism early in this century. The shrine contains the remains of many wartime leaders, including Prime Minister Tojo, who were executed as war criminals by the Allies.

Critics have suggested that instead of spending $150 million on the museum, Japan should use the money to compensate foreign victims of the war. The government has refused to make direct payments to victims like the women who were forced to work in brothels for Japanese soldiers, or to prisoners of war.

Japanese veterans organizations, on the other hand, say critics of the museum misunderstand its purpose.

"The original purpose of the museum was to pay tribute to the souls of war dead, by displaying their belongings," said Masao Horie, chairman of the Japan Veterans Association. "That way, their children can live with pride." Seisuke Okuno, head of a group opposing an apology in Parliament for World War II, said it is the critics who are trying to hijack the museum project. "The project became controversial when they tried to use the museum to depict Japanese war atrocities," he said. "But it was originally meant to be just a memorial hall for the war dead."

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