"This report together with the 2018 National Money Laundering Risk Assessment (NMLRA) and National Proliferation Financing Risk Assessment (NPFRA) provide an overview of the current illicit finance risks to the United States TF [terrorist financing] activity remains a significant concern for the United States because all terrorist groups require financial supporters, facilitators, and networks to keep funds flowing and to accomplish their destructive goals. The United States is particularly vulnerable to TF and other forms of illicit finance because much of the global economy touches the United States and U.S. financial system. The United States is the primary trading partner to dozens of other countries. Even when a U.S. person is not a party to a transaction, the value of the trade is often denominated in U.S. dollars and completed with a U.S. dollar-denominated funds transfer. In addition, physical U.S. currency is used globally as either the primary or de facto secondary functional currency or store of value."
U.S. Department of the Treasury: https://home.treasury.gov/