Leon Trotsky from "Why Marxists Oppose Individual Terrorism"
and
Terrorists bow to the spontaneity of the passionate indignation of intellectuals, who lack the ability or opportunity to connect the revolutionary struggle and the working-class movement into an integral whole. It is difficult indeed for those who have lost their belief, or who have never believed, that this is possible, to find some outlet for their indignation and revolutionary energy other than terror.
Vladimir Lenin from "What Is To Be Done"
and
A long time ago, my friend Karl Marx had their number. In 1850 he wrote a review of a couple of books by French police spies on the conspiratorial secret societies of the day -- the Weathermen of the day. In this piece, Marx took them down and shook them out as never before. Here are a couple of sentence from Marx's review, for example:
"Their job indeed consists in forestalling the process of revolutionary development, pushing it artificially into crises, making a revolution on the spur of the moment without the conditions for a revolution. For them the only condition for the revolution is a sufficient organization of their conspiracy. They are the alchemists of the revolution, and wholly share the confusion of ideas and the limitation to fixed notions of the old alchemists. They go eagerly for invented devices to achieve the revolutionary miracle: incendiary bombs, explosive contraptions with magical powers, riots, whose effects are sure to be all the more miraculous and awesome the less they have any rational basis. Busy with such plot-mongering, they have no other aim than the next overthrow of the existing government, and look with deepest disdain on a more theoretical clarification of the workers as to their class interests."
Hal Draper from "Cops, Dirty Harry, and Junious Pool"
All of these were copied shamelessly from the Marxists Internet Archive, a great place for reading.
Todd