TOKYO (AP) - In a shift away from its postwar pacifism, Japan's government overhauled its defense guidelines today, easing an arms exports ban and singling out North Korea and China as security threats.

The overhaul, which also allows the government to develop a missile defense program with the United States, has raised concerns about a slow erosion of the pacifist society Japan built after World War II.

The opposition Social Democratic Party, one of the smallest parties in parliament, criticized the government for removing self-imposed controls on military development.

The changes also have been watched uneasily by some of Japan's Asian neighbors, who suffered under Tokyo's expansionist policies in the first half of the last century. The guidelines sought to allay such fears, saying Japan's military would not go on the offensive.

"Our country, under our constitution, will adhere exclusively to self-defense," the report said. "Following our policy of not becoming a major military power that would pose a threat to other countries, we will secure civilian control."