The current generation of Japanese should not be expected to grovel over the mistakes and crimes of their grandparents. There are 1001 ways to express regret, acknowledge historical responsibility, and reflect on loss and lessons learned. I assume Abe will be dignified and appropriate. It’s really no different from a proud southener reflecting on the Civil War without being required to spend 99 percent of his time wallowing through a slavery guilt trip.
And the japs have expressed exactly none of it. Most Japs don't even know about WWII. It's not taught in school.