The Pollution of Green Socialism

Socialism always fails, both in theory - as shown by several authors - and practice - with the multiple known examples of countries that adopted such failing political theory over the past century.
To reinvent themselves and change the popular perception of their actual image, socialists have embraced environmentalism as their main political agenda. This is an obvious scheme aimed at getting more votes. But what is the history of socialism when it comes to environmentalism and sustainability?