For well over a week now, Japanese Prime Minister Shinzo Abe has been insisting that Japan's Imperial Army didn't "coerce" as many as 200,000 to work as "comfort women" in its military brothels before and during World War II.

Talk about an "inconvenient truth."

Abe apparently meant to boost his sagging popularity at home with this ill-conceived attempt at historical revisionism, but it's roiling already testy regional waters, undermining vital American interests in Asia - and needlessly dishonoring Japan.

Japan's PR nightmare began when Abe reacted to the U.S. House of Representatives' consideration last month of a resolution, introduced by Japanese-American Rep. Mike Honda (D-Calif.) that calls on Tokyo to formally apologize.

In response, Abe suggested there was no proof the women were coerced (key word - coerced!), touching off a firestorm of criticism around Asia. He dug the hole deeper by insisting Japan won't apologize again for the "comfort stations."

In fact, Japan has never really apologized. In 1993, a senior Japanese official - the chief Cabinet secretary - apologized for the government's role in the tragedy. But that "apology" didn't come from the prime minister and wasn't approved by the Diet (Japan's parliament).

Now Abe is frantically trying to moonwalk away from his comments, claiming the foreign media misunderstood. In a Sunday TV interview, he tried to stem the tide of world opinion running against him by saying the 1993 apology still stood.

He's also promising that his government will cooperate with his Liberal Democratic Party in a new investigation into the matter. Gee, I wonder what that report will conclude?

For years now, ample and near-incontrovertible evidence has shown that the Japanese army systematically strong-armed - sometimes with the help of outsider "brokers" - women in its colonies and occupied territories into sex slavery during the 1930s and 1940s.

Most of the women came from China and Korea, but the marauding Japanese army also victimized some Europeans from that continent's Asian possessions, too. The Imperial army created as many as 2,000 brothels to improve morale, prevent its soldiers from raping local women and stem the spread of debilitating sexually transmitted diseases among its troops.

Ugly, ugly stuff - on a par, in its way, with other atrocities committed by Japanese troops, such as the Rape of Nanking and the Bataan Death March.

In fairness, modern Japan isn't imperial Japan. It's democratic, peaceful - nearly pacifist - and pro-American. But Tokyo hasn't fully come to grips with its imperial past: Its school textbooks reportedly gloss over and even deny its past; controversy continues over official visits to the Yasakuni Shrine, which includes a dozen convicted WW II Class A war criminals among the 2.5 million it memorializes.

Yet Japan isn't unique in its denial and revisionism. China, for one, hasn't fully confronted Mao's frightful legacy, either. The Great Leap Forward, Cultural Revolution and other campaigns killed as many as 70 million Chinese, according to some historians.

The comfort women flap could have strategic repercussions for U.S. interests in Asia, perhaps even damage the important, generally rock-solid American-Japanese alliance.

Abe's nationalist commentary has been well-publicized in China, for starters. It's sure to enflame Chinese emotions - and thus helps justify Beijing's enormous military build-up.

China announced an 18 percent rise in its defense budget last week - following on last year's 13 percent rise, adding to more than a decade of double-digit defense-spending hikes.

The build-up isn't just about forcing reunification with Taiwan and balancing the United States. China also has its eye on settling the score with Tokyo, going back to Japan's occupation of Manchuria in the 1930s.

If Sino-Japanese tensions rise, we could see a new arms race, regional instability - and more headaches for Washington.

The controversy also complicates relations with the two Koreas. South Korea is pressuring its American ally to rein in Abe's outlandish behavior, making already tense Seoul-Washington relations even more brittle.

It interferes with efforts to deal with nuclear North Korea, too. While U.S.-North Korean nuke talks in NYC last week were all (superficial) smiles, parallel North Korean-Japanese talks in Hanoi couldn't get off the ground.

Guess why? Hardening attitudes on both sides: For Pyongyang, anger at Abe's attitude about comfort women; for Tokyo, rage over Japanese abducted by North Korean agents since the 1970s.

Hold fast on denying history? Some in Tokyo see it as a matter of national honor - but not all. Some opposition Diet members have called on Abe to have the courage to face the Japan's WWII legacy.

Honor is important in Japanese culture. But further equivocation by Abe, including pointless partisan "investigations," will only exacerbate matters and bring dishonor to Japan.

With the 70th anniversary of the Nanking Massacre just around the corner, now would be an ideal time for Tokyo to take a play of contrition from Germany's post-WWII playbook and resolve its history once and for all.

A sincere apology by Japan's PM - one approved by the Diet - for the nightmares inflicted upon these innocent women won't fully heal the wounds of Japan's colonial and World War II past, but at least it's a start.

To admit mistakes, accept responsibility and express regret is the real mark of honor. What do you say, Mr. Abe, how about some meaningful steps to finally put Japan's WWII past behind us?

Peter Brookes is a columnist forThe New York Post, a Heritage Foundation senior fellow and author of "A Devil's Triangle: Terrorism, WMD and Rogue States."