Grist: When was the last presidential race in which the two leading candidates for a major partys nomination aggressively competed over who has the best plan to address climate change? Oh, right, never.
But 2016 is a new era. This week, the Bernie Sanders and Hillary Clinton campaigns talked smack to each other on social media, fighting for the hearts of climate hawks.
It started on Wednesday, when Sanders - who last month released a very ambitious, but legislatively focused, climate plan - challenged...