CHARLOTTE, N.C. — In 2008, Al Gore strode onto the stage at Denver's Invesco Field to a hero's welcome, throwing his support behind Barack Obama to take on the "global climate crisis." When Obama takes the stage this week, Gore will be nowhere in sight. He isn't coming to the Democratic National Convention but is spending the week in New York City, anchoring coverage of the event for his network Current TV. [SNIP] While many Democrats in Charlotte were reluctant to talk about Gore for attribution, some said Gore's diminished profile — and the environmental movement's more broadly — is...