Did the Germans ruin the entire 20th Century?

Frankly this is silly. Sure the germans sent Lenin to Russia. But from whom did he get enough support to win and govern? The Russian people. Likewise, inventing communism was fairly trivial compared to the contributions of nongermans who actually took over countries under its banner. The Germans themselves didn't go for it. In fact they went to war to destroy it. Even though they failed, they still contributed greatly to postwar peace, since the soviets, after the enormous losses incurred fighting germans in WWII, had no stomach for another big war.