The United States government has effected tremendous social changes in the last four decades. Beginning with FDR's social programs, the welfare programs of the US swelled under the presidency of Lyndon Johnson and his "Great Society." Now, there is a health program that is of a magnitude comparable to no other program. Government has championed the civil rights of racial minorities and women and gays. Laws have been effected regarding hiring, pay equanimity, and rights on the job with huge bureaucratic agencies such as the EEOC to see that hiring practices, treatment on jobs, etc. are fair. Compulsory education has been made into law, as has the NO CHILD LEFT BEHIND law.
Intervening in the automobile industry, the US government under the watch of Jimmy Carter bailed out a failing Chrysler Corporation; now, under the present administration both Chrysler and General Motors have been saved from insolvency. The government has also intervened in the banking industry.
Since the World Wars, the U.S. has become the watchdog of the world and intervenes in ethnic disputes as well as attempting to bring democracy to countries to whom the concept is unfamiliar. The government provides much foreign aid. It intervenes in education with the No Child Left Behind.
Behavior is legislated when it was not in the 1940s. Whereas it was simply unethical to engage in insider-trading, for example, now it is illegal. It is a law that a driver and /or passenger ride with seat belts fastened.
Departments such as the Federal Drug Administration and the USDA seek to protect people through safeguards put on the purchase and quantity of certain things. The government is much more involved in people's lives.
Immigration laws are much more relaxed now compared to in the 1940s. More and more taxes are being applied to goods in the U.S.