Why did Czar Nicholas want to enter world war 1?

The Czar entered WW I because he had a mutual defense pact with France and England. Although Germany began by invading France, they might have invaded Russia instead, and if they had, then Russia would have wanted France and England to come to its defense. Everybody was afraid of Germany. Furthermore, if Russia had ignored the mutual defense pact and simply allowed Germany to take over France, the time would have come when Germany would be finished with the pacification of France, and would be ready to take over other countries. Russia's time would come eventually. It was actually easier for Russia to join the fight in 1914, rather than waiting until Germany had become an even larger, stronger opponent.