A revolution will come, history highlights that is how change happens and it happens regularly. After Marx and the socialist political movements that arose from his writings that tried to play within the system, ultimately making little impact after the initial wave whilst joining the game of musical chairs I doubt there will be any larger movement that will attempt the same thing again. Revolution doesn't necessary mean it will be the kind that Brand wants, especially as much of the real problems on the horizon are only really espoused by those that are often peaceful and revolution requires people that will stomp more than a few heads. Plus no real viable economic alternative has presented itself whilst we have cultures that are insistent on population growth, want everything and want it now at the expense of other nations, and a system that has to maintain food production or the heads of the system get got. When revolution does happen it often comes when things have come to an all time low and people are pushed to extreme acts, we are far away from that at the moment but the signs are there and should start to see the first waves in the 2030's to 2050's if the ecologists are correct, unless there is a big technological revolution.