Many Japanese people have recognized that the Japan-U.S. Security Treaty has been the most important base for defense of Japan. It was excellent history that only the USA occupied Japan instead of the Soviet Union after the Second World War.
After that, so-called the Cold War started, and finally the Soviet Union collapsed. Of course Japan should obey the military system decided by the USA. Japan and the USA have not been the equal partner after the Second World War.
The USA has protected Japan against the Soviet Union during the Cold War, but the military situation has been changing after the Cold War.
The war in this century is terrorism. It's said that terrorism is the war between poor Islam extremists and rich Western countries. I think that terrorism is tha war between poverty and wealth.
The military power is supported by money, that is, the economy has controlled the military power. Poor people are poor, and so they want to fight against wealth. Poor people don't need the good economy for the war. What can rich people do against poor enemy? It's not the war, but the support for them.