Whose fault was World War 1?

It is agreed by most that World War One was one of the most devastating events ever to take place on Earth, but the argument of which nation should carry the burden of responsibility rages on. However, many undisputable facts show that this Great War would never have happened had it not been for the actions of Germany and Austria-Hungry. Once the heir to their throne was assassinated, Austria-Hungry looked for no other possibility but …

…could not ignore alliances they had made and Germany knew this. Austria-Hungary knew that Russia would react later, if not sooner, to their declaration of war on Serbia. Austria-Hungary and Germany knew the consequences of their actions and still took them. These two nations started the chain reaction which ignited World War One. One cannot start a fire without a spark. Austria-Hungary was the spark and Germany was the gasoline to keep the fire going.