How have the size and functions of government in the United States changed during the last century?

During the last century, government has become both larger and more centralized. A century ago, the role of the federal government was limited. It provided national defense and was involved in transportation (construction of roads and canals), but not much else. As recently as 1960, national defense accounted for more than half of the federal expenditures. During the last four decades, federal expenditures for income transfers and health-care programs have grown rapidly. Expenditures on these programs now account for nearly three-fifths of the federal budget, compared to 18 percent for national defense. Therefore, in contrast with its limited function of a century ago, the federal government is now heavily involved in the taxation of some in order to provide income transfers and health care for others, particularly the elderly.