Who monitors the cargo ships coming to US?

Are there security forces in place to watch the foreign cargo ships coming into our ports, I'm thinking of outlaws/pirates that might attempt to board and do harm,etc.Who monitors the cargo ships coming to US?
the port authorityWho monitors the cargo ships coming to US?
Dubai monitors 22 U.S. ports.
U.S. Coast Guard and Customs when they come to ports and unload goods
coast gaurds and u.s. employees
the Department of Homeland Security. The United States Coast Guard monitors the ships and the lakes and what have you
There are a lot of companies who do this. The Coast Guard and Port Authority handle security.
Coastguard, navy, port authorities, local police, FBI.