 China has said, along with India, that it has a policy of no first use of nuclear weapons. Now there appear to be signs that this is no longer the case. And, of course, being so ready with nuclear weapons as tensions get very high over Taiwan is really extremely worrying. Jane Wang, you spoke with us earlier this summer. We focused on the tension between the U.S. and China over Taiwan's status as a self-ruled democracy. Here's Tong Zhao's what-if scenario.