People warned Marc Benioff, the billionaire chief executive of Salesforce, not to bother talking to the White House about global warming. But Mr. Benioff, a tech mogul and environmental philanthropist, felt sure he had found a climate change solution that even President Trump could love: Planting trees. Never mind that the idea came from former Vice President Al Gore, who has demanded Mr. Trump’s resignation over his energy policies. Never mind that Mr. Trump has begun the yearlong process of withdrawing America from the Paris Agreement on climate change, mocked Greta Thunberg, the teenage climate activist, and worked to eliminate every regulation aimed at reducing planet-warming emissions. The idea of planting one trillion trees had one enormous political advantage: It was practically sacrifice-free, no war on coal, no transition from fossil fuels, no energy conservation or investment in renewable sources of power that Mr. […]