Section 8 of the U.S. Constitution grants Congress the power to “regulate commerce with foreign nations and among the several states, and with the Indian tribes.” This section is referred to as the “commerce clause.” Originally Congress was given this power in order to block protectionist state restrictions. The original 13 states were, in many ways, like small, independent countries and, without the commerce clause, could have chosen to restrict IMPORTS from other states. For example, for over 100 years New Jersey financed its state government by levying a transport tax on wagons moving goods from Philadelphia to New York. The U.S. Supreme Court has indicated in recent decades that Congress has broad authority to regulate commerce under the commerce clause, and that even internal state commerce affecting interstate commerce can be regulated. Many federal statutes, including some civil-rights laws, are constitutionally based on the commerce clause. As a practical matter, the commerce clause, in conjunction with the supremacy clause, supports the common economic market of the United States by minimizing state regulatory TRADE BARRIERS. Congressional regulation of U.S. foreign commerce, which has been much more controversial, is discussed under EXTRATERRITORIAL JURISDICTION.