I enjoy Studio Ghibli movies. However, this movie has a straightforward and simplistic essence to it - a simple plot that just shows you how two children deal with the changes around them. They lost their parents, and a family friend (whom they called Aunt because it's the Asian/Japanese cultural way to referring to someone close to their mother's age out of respect) takes them in during WWII.
I gave it a three because it did not touch me as many of the other reviewers had claimed. However, it was a good representation of what happened at that time. Many reviewers said that this movie isn't a good presentation of what happened in the war and that the Japanese are using it to deny the responsibility for their cruelties in that war. I don't feel like that that is so as the story just depicts their point of view, which is that's their country is getting bombs and people were suffering because they were bombed. There was no acceptance or denial of who was right or wrong, but just simple common sense. I think that was the purpose of this movie - relaying the situation of the war through a story of a young pair of siblings. The plot was linear and not entertaining to me. I felt like the story didn't make sense at times though - the choices the young boy made, but he was only 14. Perhaps with immaturity and lack of common sense, he chose the wrong choices that led to the unfortunate ending.