Really - I thought Hitler invading Poland, Russia, Checkozlyavakia, had something to do w that along a Japan bombing us.
England (egged on by churchill and his ilk) decided to declare war on germany over something that had nothing at all to do with british safety, despite efforts by germany to avoid war with britain. Britain's decision to declare war on germany set the whole thing in motion-they turned small border issues into a global meltdown. They brought in france with them, as well as their global empire, and eventually churchill convinced roosevelt to bring the US into the european conflict as well.
Germany wanted no part of a war with the Allies. They would have eventually fought the soviet union, and destroyed communism in its cradle, but the World War it became sits squarely on englands and churchill's shoulders. They are the ones who made the decision to declare war when their nation faced no military threat at all