No, it's _the other way around_. Those Green activists who are either professionals or belong to the better-off segment of the working class should take part in environmental justice movements to _learn_ something about class struggles, from the urban poor as well as what environmental justice struggles by their nature teach them.
I don't think that the urban poor in the core capitalist countries--especially those who are politically aware and active in environmental justice movements--are ignorant of global warming and other environmental issues. They just don't have as much time to devote to those issues as better-off people do; besides, there are more pressing concerns for the urban poor.
This doesn't mean that professionals and better-off workers have nothing to offer to the struggles of the urban poor. They do, especially in terms of expert knowledge, legal assistance, contribution of time and money, linkage between the urban poor and those who reside outside the cities, and so on.
However, those Greens whom Michael Perelman calls 'middle class' ought _not_ to think of themselves as 'educators' of the 'less fortunate.' That's not the way to go about creating unity.
Yoshie