While there has been much discussion about China's growing force of short-range ballistic missiles, Beijing has also deployed new warplanes, destroyers, submarines, anti-ship missiles and surface-to-air missiles, many of which it bought from Russia.
The Sub Aquatics Development Corporation of Vancouver, British Columbia, was the first company to design and deploy new submarines for public underwater excursions, starting at Grand Cayman.
Iran would be able to deploy anti-ship cruise missiles, submarines, mines and thousands of small watercraft that could be used in "swarm" attacks against shipping if the ayatollahs decided to impose a blockade.
Although they occasionally deploy true submarines, most are self-propelled semi-submersibles, where a portion of the craft remains above water at all times.
All deployed ships, submarines and aircraft would still be available for emergency operations, the officials said.
As the Cold War intensified in 1961, the United States deployed Polaris ballistic missiles, and submarines, in the Firth of Clyde's Holy Loch.
Denmark is one of several NATO member states whose navies do not deploy submarines.
"As a matter of fact, I am so sure you are lying to me that we have deployed submarines around your island to ensure your ships do not land the missiles."
The navy deployed all active-duty combatant ships, submarines, fighter jets and the special operations forces, including the entire division of Marines and the naval establishments to cover the entire gamut of naval operations.
Iran has also deployed submarines and warships off Yemen's coast, in the Gulf of Aden and Red Sea, ostensibly to conduct anti-piracy operations.