answer: John thinks a lot of wars nowadays are civil wars and cutting off the financial support of different ethnic groups will end the war.
documents: #Person1#: Hey, John! What do you think are the main causes of war today?
  #Person2#: It's hard to say! But it seems that a lot of wars nowadays are civil wars. People from different ethnic groups in the same country sometimes fight for power in that country.
  #Person1#: Yeah, several of those civil wars have been going on for years and years. It seems they will never end.
  #Person2#: How do you think they could be ended?
  #Person1#: I don't think that there is any easy way.
  #Person2#: I think one better way to stop it is to cut off their financial support.
  #Person1#: Yeah, you are right!