Last week French environmental minister Nicolas Hulot, once a prominent supporter of President Emmanuel Macron, threw in the towel. “I don’t want to lie anymore. I don’t want to create the illusion that my presence in the government means that we are on top of [environmental] issues,” he said during a live broadcast announcing his resignation.

Mr. Hulot is not alone among environmentalists in denouncing the hypocrisy and inadequacy of government action on climate change. The Paris accords are “a fraud, really, a fake,” said...