The Environmental Protection Agency’s “Clean Power Plan” unleashed a firestorm of criticism — but New York has been well ahead of the debate by setting out the most ambitious environmental targets in the country. In fact, Governor Andrew Cuomo has staked his reputation on achieving “50 by 30,” meaning that by 2030 the state would get half of its electricity from renewable energy sources. This is a bold but achievable goal. If it were embraced by today’s presidential candidates and then embraced nationally, the United States would make a huge contribution to preventing climate change.

“If” is the key word, unfortunately.