I always like this quote from Rosa when it comes to Kautsky and his ilk:

"It is especially astonishing to observe how this industrious man (Kautsky), by his tireless labor of peaceful and methodical writing during the four years of the World War, has torn one hole after another in the fabric of socialism. It is a labor from which socialism emerges riddled like a sieve, without a whole spot left in it."
"The party of Lenin was the only one which grasped the mandate and duty of a truly revolutionary party and which, by the slogan – “All power in the hands of the proletariat and peasantry” – insured the continued development of the revolution.
Thereby the Bolsheviks solved the famous problem of “winning a majority of the people,” which problem has ever weighed on the German Social-Democracy like a nightmare. As bred-in-the-bone disciples of parliamentary cretinism, these German Social-Democrats have sought to apply to revolutions the home-made wisdom of the parliamentary nursery: in order to carry anything, you must first have a majority. The same, they say, applies to a revolution: first let’s become a “majority.” The true dialectic of revolutions, however, stands this wisdom of parliamentary moles on its head: not through a majority, but through revolutionary tactics to a majority – that’s the way the road runs."
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