2 billion mu cultivated land will be made at the total cost of RMB ￥ 200 trillion within 200 years (calculated per the currency value in 2000) while the service life of the ACL is designed to be 10,000 years. Is it worthwhile at such a high cost and the amount of efforts involved? I would say yes based on the reasons as follows. 1) The four problems in China can be completely solved, i.e. self-sufficiency in grain, environmental protection, water resource shortage and employment for millions of people.2) China will embark on the road towards cyclic development. We will solve the problems created by ourselves for the benefits of our offspring. 3) Let's make such a calculation. Suppose we need to import 0.1 billion grain each year at the international grain price of $500-1000/t. Then it will be $10-20 trillion for a period of 200 years and $500-1000 trillion for 10,000 years. Who can guarantee the self-sufficiency in grain in China in 200 years? It could also be a possibility that the US may need to import grain in 200 years.