Dreams are often stories which seem totally unrelated to real life but which pinpoint key concepts and emotions which are dominating our mind. What you must first do is to look through the various portions of the dream and see if you can detect some key associations. If you can connect a dream to real life then it is likely that the dream is linked to that subject. Ask yourself key questions such as
1. The dream starts on a note of war and then ends in a tone of peace. The dream could portray a thought such as "I thought at first he was confronting me but actually things ended calmly"
2. The dream features very old weapons of war - the fokker tri-plane and sopwith camel are from the very early days of aviation. Could this hint at someone who is getting on in years. Did someone talk about some conflict with you who was much older.
3. Japan. One feature of world war two was that America and its allies treated their former enemies very well. They hoped that such treatment would make japan and germany as friends in the future. This could be a metaphor for a thought such as "I know we have had our differences but if I treat him well then we could start to become friends". Does such a theme seem relevant in your life right now? Dreams are in the here and now so they will often be symbolic of thoughts which we might tell a friend or write down in a diary.
4. The Japanese song. Think on an emotional level and see if this makes you think of as key emotion right now. It seems to be linked to emotions such as sorrow or loneliness. If this makes you think of a thought or emotion right now then the dream could link to that situation in real life.
Only you can make these connections. Analysing someone else's dreams is not easy as they are very personal and interpreting them is very difficult. When you get a dream try to link it by establishing associations. Is there any connections which come to mind? Try these two links from my website as they may help you make further associations.
Warfare in dreams
Music in dreams