Without knowledge of the specifics of the American decision-making system, it is impossible to understand the individual steps of the administration to form and implement economic policy. This system is based on the mechanism of bringing to a common denominator the national interests and multidirectional interests of various corporations, small business, nonprofit organizations and public groups that have legal channels of pressure on the legislative branch and the executive branch of government. The article analyzes the institutions, mechanisms and constraints of economic policy formation, its decision-making process in the United States. The specificity of the decision-making process is particularly evident in the formation of fiscal policy. Here interests of parties, administration and the congress, the federal center and states, lobbyists of different levels collide. The election of "non-system" president D. Trump, and his sharp turns in domestic and foreign economic policy have raised questions about the sustainability of the system of decision-making and its effectiveness within the framework of the division of power between the legislative, executive and judicial branches in the United States.