We made a mistake getting into that war. The Germans were right to fear encirclement by France and Russia, and the Austrians certainly had a valid cause for war with Serbia. After all, when our sovereign territory was violated around the same time by Villa, we sent troops into Mexico. Hell, we occupied Vera Cruz, if I'm not mistaken, merely because the Mexicans insulted our flag.
The Russians caused WWI by mobilizing. The Germans were to blame for bringing the French in, which they had to do because they had only one war plan, but there is no way the French would have simply stood by while the Germans and Austrians fought the Russians.
As to Belgium, the British and French had their own plans for moving into Belgian territory and probably would have executed them if the Germans hadn't invaded first.
It's not black and white, but the Germans definitely don't deserve the rap they get for WWI.
In deed, the neo-cons have cause to argue as the Germans and Austrians were fighting a 'pre-emptive war.'
God bless the last of the warrior poets, their lives extinguished on the Western Front, 1914-1918.