I do not agree with this statement to any great degree.
Germany did help to cause the war. Germany wanted its "place in the sun" and was acting somewhat aggressively to get it. However, this does not mean that the war was Germany's fault.
Instead, we have to blame the other countries as well. They felt threatened by Germany's desire to become a major power. If they had taken the attitude that Germany's rise to greater power was no big deal, they would not have had to engage in the arms race and the creation of alliances that helped to lead to the war.
There is plenty of blame for both sides in the war. Germany did act aggressively, but England and France, in particular, can be said to have overreacted to Germany's efforts to become more nearly equal in power.