Austria was facing (in Serbia) a smaller and less organized nation… the disagreement was over the idea that the Serbs in the Austro-Hungarian Empire should be able to become part of Serbia or at least a nation of their own. On the face of it it should have been a slam dunk to beat Serbia.Russia had had a vision (Pan-Slavism) of getting all the Slavs absorbed into (or at least aligned with) Russia... hence their backing of Serbia when the Austrian ultimatums came.The domino effect, the rest of the nations rushing to war, was the result of the old balance of power situation in Europe (result of the Congress of Vienna after the Napoleonic Wars); Austria threatened the peace that had been achieved by the C of V. With the exceptions of several failed revolutions, a couple of successful wars of unification, a border squabble or two, and the Crimean War; the C of V had prevented a continental war for a century. This was about to end....In the meantime the quest for overseas empires and the reampent militarism of the era added fuel to the potential confligation. The killing of the Archduke was just the spark needed to set it off.