If you are noticing international problems that are arising because Japan has become a pacifist nation (Chinese and North Korean aggression) or because the Europeans are hostile to Israel and unwilling to share any burdens of global policing (Libya, Syria, Egypt, Iran...), you may have to look at the United States as the reason for this problem.
The United States has been willingly acting as a global policeman since World War II. This willingness has allowed Europeans and the Japanese to assume the position of helpless nations unwilling to fund a reasonable standing military.
That is part of the reason. The real problem comes from the fact that the United States, at the end of WWII, designed Europe and Japan to be pacifists.
The Japanese Constitution actually defines Japan as a country without a military. Over the intervening sixty years several generations have grown up with a pure pacifist mentality. I see no way that that can be changed.
The United States did everything possible to create a European Union with the intention of ending the millennia long internecine warfare in Europe. The U.S. created a unified NATO that could confront Soviet communism. It diffused European nationalism. The net effect has been to create a pacifist Europe over two generations. Europeans now abhor nation-states that need to defend themselves, like Israel.
We have succeeded in making sure that we have no allies to support us in global policing responsibilities and can never look forward to such allies again.
Someone might stop me and ask about the European staffed peace forces on the Lebanon border, the Golan Heights and Sinai borders and I can only respond by pointing out how quickly these peace forces evaporate in times of trouble. Pacifists pretending to be soldiers.
China and a few other countries are not part of this pacifist landscape that we have created.
We have no choice about how to deal with this as our own creation bites us in the foot. We must remain the global policeman. Fortunately, Canada, has understood what has happened and keeps encouraging us to act responsibly.