This is fantastic:

The nation’s largest manufacturing union, the United Steelworkers of America, and the nation’s largest environmental group, the Sierra Club, yesterday announced the formation of an alliance that will do something that labor and environmentalists rarely do: cooperate.

This tells me that the Sierra Club is hip to many of the criticisms of environmentalism raised in the Death debate and recognizes the need to build coalitions, reconnect with progressivism’s blue collar roots, and emphasize workaday concerns like jobs and health. This will allow both the club and the union to reach new audiences.

Still, let’s not get too excited. This is not a sea change for the steelworkers union. It’s been part of the environmental coalition before.

We’ll know a corner’s been turned when we see coalitions with unions of autoworkers, or mine workers, or coal-fired utility workers. Once those unions see that their best interests are served by sensible regulation and private-sector innovation — not by siding with corporate fat cats fighting tooth and nail to keep old, tired, backward-looking industrial practices afloat — we’ll know the message is sinking in.