This NY Times piece about motivating both liberals and conservatives to engage on climate change is worth reading.   Back in the 1990s, applied economists wrestled with the general issue of what exogenous variables have a monotonic impact on raising the probability of taking a given action.  See page 1343 of this paper for an example from health economics.  In the case of environmental policy, the same "treatment" (i.e hearing about Al Gore's new thoughts) may have different consequences for different people.   Some people who are sympathetic to his world view will be "turned on" by his new ideas while other people may be "turned off". A more sophisticated environmental movement would figure out how to motivate rather than demonize political conservatives.  Dora Costa and I explored some of these issues in this 2013 JEEA paper.