Richard Pipes in *The Russian Revolution*, asking why Russia went to war when the risks (especially after the war with Japan) were so obvious, argues (p. 195-6) that
"Socialist writers attribute tsarism's involvement to the pressures of Western democracies whom Russia owed vast amounts of money. For Russian conservatives, Russia acted out of a selfless devotion to the alliance... [which] earned her no gratitude...
"Such explanations are unconvincing. Imperial Russia entered into defensive alliances and honored her commitments neither in response to Allied pressures nor from altruistic motives, but from soundly perceived self-interest. Long before 1914 Russian statesmen had a good notion of the designs Germany had on her. These called for the dismemberment of the Empire and German economic mastery over Russia and her borderlands. Post-World War II archival research has confirmed that German political, military, and business circles regarded the breakup of Russia and control over her resources as essential to Germany's global aspirations. Berlin assigned high priority to neutralizing the Russian military threat and the related prospect of a two-front war as well as to gaining access to Russia's human and material wealth with which to match that of France and Britain.
"Given Germany's *Russlandpolitik* after the dismissal of Bismarck, the choice before the rulers of Russia was not whether to withdraw into isolation or to join in great-power politics, with all the risks that this entailed: this had been decided for her by Germany. Her choice lay between facing Germany alone or acting in partnership with France and possibly England. Posed in this manner, the question answered itself. Unless Russia was prepared to give up her empire, shrink to the territory of seventeenth-century Muscovy, and acquiesce to the status of a German colony, she had to coordinate her military plans with the Western democracies. The alternative was to stand by while Germany smashed France, as she was certain ro do if her eastern flank was secure, and then transferred her armies east to dispose of Russia'..."
Unfortunately, the only sources Pipes gives for his characterization of Germany's pre-1914 designs on Russia are Fritz Fischer's *War of Illusions* and *Germany's Aims in the First World War*, and I am a little bit rusty about the "Fischer controversy"
http://en.wikipedia.org/wiki/Fritz_Fischer and specifically about what evidence Fischer gives for Germany's pre-1914 intentions vis-à-vis Russia...