When Sarah Lande served Xi Jinping green bean casserole at a potluck in small-town Muscatine, Iowa, in 1985, she never imagined the young Chinese official would become the leader-for-life of his country — and a fierce opponent of the US. But this week Lande, now 85, will be reunited with Xi in San Francisco, when he attends the Asia-Pacific Economic Cooperation summit, marking almost four decades of a very unlikely friendship. Xi Jinping will first meet with President Biden on Wednesday during the summit to discuss hot button issues – from trade and tensions over Taiwan, to the spy balloon…