The simple answer is no, but… Thanks to the Dodd-Frank Act.
There are a good number of offshore international Forex brokers that accept US citizens and residents. However, with the Dodd-Frank Act implemented in 2010, many offshore international Forex brokers do not accept US citizens.
The Dodd-Frank Act became operational on July 21, 2010. It is aimed to regulate financial markets including stocks, futures, options and Forex. The Dodd-Frank Act requires that every Forex broker must register with both Commodity Futures Trading Commission (CFTC) and National Futures Association (NFA) if it wants to do business with US citizens and residents. Many foreign Forex brokers find this a big hassle and choose not to accept the US customers.
A few regulated foreign brokers who still accept US customers are: