Personally, I do not at all believe that there is any form of apology that Shinzo Abe could have given that would fully mollify the South Koreans and Chinese. The South Koreans at least recognised that a deeper apology was given by former Prime Minister Murayama and asked why he did not repeat this as Junichiro Koizumi did in 2005, though their response at the time Murayama and Koizumi made their apologies did not seem to recognise them as full apologies either. The Chinese, on the other hand, seem not to recognise that any real apology of any kind has ever been made by Japan's leaders.
The reasons for this have little to do with lasting memories of Japanese war crimes and crimes against humanity in the years between 1931 and 1945, which were numerous and terrible. This can be stated with confidence simply because in the decades immediately following the war criticism of Japan for being insufficiently contrite was so much more muted, both from China and Korea. For example, the document that established relations between the People's Republic of China and Japan dealt with war-guilt in only two places. Here:
"The Japanese side is keenly aware of Japan's responsibility for causing enormous damages in the past to the Chinese people through war and deeply reproaches itself . . . The Chinese side welcomes this"And here:
"The Government of the People's Republic of China declares that in the interest of friendship between the peoples of China and Japan, it renounces its demand for war indemnities from Japan"
The statement felt no need to note insufficient contrition on the part of the Japanese, nor was this expressed by any of the officials responsible for re-establishing relations on the Chinese side either. Such misgivings, if they existed, had clearly be shelved for later generations to address. China at that time was supportive of various Japanese initiatives, including their resumption of sovereignty over Okinawa, despite later claims from people like (PLA General) Luo Yuan within China that Okinawa really belongs to them.
In Chinese affairs the change from a broadly-friendly position towards Japan to one suspicious towards Japan came later. Whilst Taiwan under the ROC, and to a less extent Hong Kong, saw protests about the 1972 transfer of administrative rights over the Senkaku Islands, these were not echoed in mainland China. Instead it was with the decline in communist ideology in mainland China and its replacement with nationalist rhetoric that differences with Japan and the war became an endless source of material to inspire such sentiment amongst young people through the education system and the media.
That this was so was instantly apparent to anyone who observed the 2005 anti-Japanese protests, sparked by the approval of denialist text-books for use in at most 18 schools in Japan, which were overwhelmingly made up of young people, and for which supporting sentiment was most widely expressed amongst young people. As the sellers of Japanese goods and Japan-themed restaurants tried to protect themselves against attack by displaying Chinese flags and poster-sized pictures of Mao Zedong in their windows, the people who marched outside their doors were overwhelmingly of university age. In Nanjing, where I was working and studying at the time, wide-scale protest was headed off by the authorities after it had outgrown its usefulness by the simple expedient of threatening to expel students who took part.
Whilst the issue of whether Japan's leadership and government has been contrite enough about the war, done enough to educate people as to what actually happened, and done enough to counter those who deny that Japanese war crimes occurred or that Japan was responsible for the war, is a real one. However, it's clear that in the People's Republic at least it is basically a tool for use both in domestic control and in external diplomacy.
In countries which suffered at the hands of that Japanese where the impact of nationalism is less strongly felt, including my own, such things are commonly regarded as of lesser importance than the trade a cultural links with Japan. Whilst the UK did not suffer even nearly as badly as China did at the hands of the Japanese, I heard similar sentiments expressed in Malaysia when I visited there back in 2009, in the Philippines when I visited there in 2003, and from Indonesians I have been acquainted with - all places which suffered greatly at the hands of the Japanese.
Abe's speech also contained one very sane statement:
"In Japan, the postwar generations now exceed eighty per cent of its population. We must not let our children, grandchildren, and even further generations to come, who have nothing to do with that war, be predestined to apologize. Still, even so, we Japanese, across generations, must squarely face the history of the past. We have the responsibility to inherit the past, in all humbleness, and pass it on to the future."At some point the Second World War will merge into the past and its grievances will have to be set to one side. It is certainly illogical to demand apologies for events that occurred before the people who you are demanding them from were even born. This point is fast approaching, and these demands for apologies cannot be allowed to continue beyond it. The alternative is the idea that it correct to inflict some kind of biblical punishment "unto the third and fourth generation" on the Japanese people.
[Picture: The letter sent to former British inmates of Japanese POW camps by the King welcoming them on their return to the UK]