Now, suppose that U.S. policymakers do not actually care about pollution, but merely about real purchasing power of U.S. incomes. What is the effect of an increase in θ on the terms of trade, and on U.S. and Chinese welfare? Does your answer depend on other assumptions not specified in the question (and if so, how)? Would the U.S. government ever have an incentive to increase θ (say, by increasing the amount of paperwork and time used up in complying with the pollution standard)? Explain clearly.