Japan's Emperor Akihito wrapped up a historic five-day visit to the Philippines yesterday, and his message - let war be a reminder of the value of peace - was heard loud and clear in a nation still carrying scars of World War II but eager for allies as it squares off with China.

The visit was symbolic. No politics-altering speeches or deals were expected.

But for most Filipinos, the sight of Japan's revered monarch bowing to apologise for his nation's wartime past suggested that Japan, once a hated enemy, could now be trusted.

That alliance becomes even more crucial as China's shadow looms large over both countries.

"This visit of Emperor Akihito... is much more than just a goodwill gesture meant to bury painful memories of war losses and grief. It is, most of all, an acknowledgement that, in times of crisis, we need all the friends we can summon," the Philippine Daily Inquirer said in an editorial.

The Philippines and Japan have both been wrestling with China's push into waters near their borders.

China claims nearly all the 35 million sq km South China Sea, including parts that the Philippines insists are inside its exclusive economic zone. Vietnam, Malaysia, Taiwan and Brunei also have overlapping claims.

Japan, meanwhile, is locked in a dispute with China over the Senkaku islands in the East China Sea.

The Philippines has said it is open to letting Japan use its military bases so that the Japanese navy can go on patrols around the South China Sea, serving as a counter-balance to China's growing naval presence in the area.

Emperor Akihito, 82, had framed his pacifist message even before he left Tokyo, saying the hundreds of thousands who lost their lives in the Philippines - Filipinos, Japanese and Americans - during the war should always be remembered.

He repeated that message wherever he went: at a national cemetery for Filipino soldiers, a state banquet hosted by President Benigno Aquino and a garden memorial for Japan's war dead.

"Japan's post-war positive record has done much to make the message of peace resonate among Filipinos who embrace it," said military historian Jose Antonio Custodio.

He said Japan has been apologetic, and it has become a major contributor to Philippine growth.

Younger Filipinos, with their fondness for manga, Shibuya fashion and sushi, have also embraced Japanese culture.

"All these provide the basis for the ready acceptance of and belief in Japan's altruistic and peaceful image to Filipinos," said Mr Custodio.

Still, scars remain.

About a million Filipinos died during the Japanese occupation of the Philippines from 1942 to 1945.

Protests organised by groups supporting the few surviving women forced by Japanese imperial troops to work in brothels during World War II dogged the visit.

The women sought an audience with Emperor Akihito, and demanded that President Benigno Aquino take up their cause.

Leftist groups, meanwhile, criticised the Emperor's visit as an attempt by the nationalist government of Prime Minister Shinzo Abe to mask its right-ward shift.

"What is worrisome now is the drive of the Shinzo Abe regime to revive Japanese militarism and allow the deployment of Japanese troops overseas...

"The Emperor remains a representative of that policy," said Mr Renato Reyes, spokesman for the left-leaning Bayan Muna (Nation First) group.

But these were minority opinions.

"Overwhelmingly, majority of online reactions have been favourable to the visit. In fact, the few negative comments have been met with a lot of criticism from those in favour of the visit," said Mr Custodio.