The sharp increase in terrorism and terrorist threats in recent years has heightened the awareness of maritime nations for the need to implement security measures to protect vessels, shipping interest and ports. The maritime shipment of cargo is vitally important to the global economy, and accordingly the United States and other maritime nations are endeavoring to assure the safety of ports without severely hindering maritime trade. The containerized movement of cargo, while more efficient than the break bulk carriage of cargo, also creates the potential vulnerability of security, given that a sealed container could potentially conceal dangerous or illegal contents including biological or nuclear weapons. In addition to domestic security problems, United States vessels encounter numerous security threats during voyages on the high seas. The combined attempts of the United States and other maritime nations in combating current security issues are discussed below.