Almost every major advance of the US economy has been nurtured or facilitated at some point by the active involvement and encouragement of the national government. It's been a partnership - sometimes uneasy, sometimes close, but a partnership - between government and free enterprise, that has led the development of the US economy. This role of the national government was deliberately written into the Constitution, and touches directly on Constitutional issues that the left has ignored, but which the wrong-wing has long waged a smear campaign against. These issues go to the heart of the question: What is the role and purpose of government? They include such specific issues as the General Welfare clause, states rights, implied versus enumerated powers, and the reach and scope of the Commerce clause.
Contrary to the idealized wrong-wing myth of the U.S. economy being founded on the principles of laissez-faire, the framers of the Constitution deliberately set out to create a central government strong enough to force the thirteen states into one national economy. To do this, the national government undertook a number of programs and policies to build and strengthen the national economy by encouraging and protecting manufactures and commerce, establishing a national banking system, and promoting and directly assisting the development of transportation.