Washington Post: Al Gore must be kidding. The former vice president, now in his second career as a climate Cassandra, has spent the past few weeks pushing the notion that the United States can be “repowered” — that all its electricity needs can be met without producing greenhouse gases. He says it can be done within a decade. At the Democratic National Convention last week, he told the crowd in Denver that “we have everything we need” to start solving the climate crisis, …