Actually taxes are used for "social engineering" all the time. Most of the deductions that are itemized have to do with social engineering, from charity to home ownership (we have thought it best for people to own their own homes since colonial times--property owners make better citizens) to deductions for children, dependents of all sorts, education & tuition, and let's not forget George B's recently floated proposal to use tax credits to encourage people to marry and to stay together. And an adoption credit. The list goes on and on. We make judgements about some of the kinds of activities we want people to engage in, and we tax accordingly.
Remember what the first paragraph of the Constitution says, "We the People of the United States, in order to form a more perfect Union, establish justice,... promote the general welfare...." If you read The Federalist Papers, the founders presumed that there would be a certain number of people who were "natural aristocrats", that is, who possessed a certain nobility of character and intelligence, who could rise above their own interests, passing and executing laws that promote the common good, not just the good of one class or one group of people. So far, they've been right enough of the time to keep the country together. But they knew that there were no guarantees, and if the right people weren't running the country, it could and would fall apart due to the inherent selfishness of the many. Check out Fed 10, 14, 51, 63 for starters. I'm sure there are other relevant ones, but can't think of them offhand (I'm going by memory here, so there may be some that are more relevant than those). If you want, I can try checking it out again this weekend.
Market Data 
Markets 
AI
