The U.S. military is reported to be testing a missile-armed, remote-controlled robotic boats developed by Israel's Rafael Advanced Defenses Systems, possibly to bolster its naval capabilities in the Persian Gulf where it's locked in a mainly maritime confrontation with Iran.

The mass-circulation Yedioth Ahronoth reports that the Americans see a possible use for the 30-foot unmanned Protector boats, which can carry one bow-mounted 7.62mm machine gun or anti-ship missiles, against Iranian suicide boats manned by Revolutionary Guards.

The small Iranian vessels are intended to "either block or attack any American aircraft carrier making its way through the Strait of Hormuz," the newspaper said.

Iran has threatened to close that narrow waterway, the only way in and out of the Persian Gulf, if it is attacked. One-third of the world's oil supplies pass through the 112-mile channel every day.

The Israeli navy is reported to be operating Protectors armed with multipurpose anti-armor Spike missiles, which are also built by Haifa's Rafael. Britain's BAE Systems and Lockheed Martin helped develop the unmanned boats.

Yedioth reports that last Wednesday the U.S. Navy test-fired six missiles from several unmanned surface vessels off the coast of Maryland. The daily gave no other details but observed that "all ... were reportedly accurate."

Wired magazine, which monitors new weapons systems, quoted Mark Moses, the U.S. Navy's drone boats program manager, as saying, "The tests are a significant step forward in weaponizing surface unmanned combat capability."

The Protectors "could be used for a number of applications, including harbor security, and in various defensive operations and scenarios, which are of primary concern for the Navy," Moses added.

Yedioth reported that any U.S. contract to buy Protector is "expected to amount to millions of dollars." But it noted that the Americans may arm any boats it buys with U.S.-built missiles, such as the Javelin or the Hellfire, rather than Israeli-made weapons.

These are both combat-proven systems modified for naval deployment. The FGM-148 fire-and-forget Javelin anti-tank weapon is built by Raytheon and Lockheed Martin. The AGM-114 Hellfire is produced by Lockheed Martin.

The Protector is already in service with the Israeli and Singaporean navies. It can reach speeds of 42 miles per hour. Its machine gun is capable of staying on target even in rough seas.

The boat carries radar and sonar systems and at least four cameras to identify targets, with electro-optical systems to provide 3-D imaging.

Noam Brock, who headed the Rafael team that developed the Protector, said the boat can operate at night and cope with heavy seas.

"Its systems are so advanced they can track the flight of a single bird," he said in 2006.

"The next step ... will be to equip the system with greater attack capabilities." That seems to have been achieved.

Rafael officials also see Protector having an anti-piracy mission, possibly against the Somalia pirate gangs marauding across the Indian Ocean, or the growing threat in the Atlantic off West Africa, a major oil-producing zone.

Other USVs are also on the market. One is the 21-foot Interceptor manufactured by Marine Robotic Vessels International of Florida. It can make speeds of 55 mph and has reportedly emphasized reconnaissance over firepower.

In late 2007, British defense firm Qineteq unveiled the jet-ski-sized Sentry, which was designed for intruder investigation.

It's likely that the Israeli navy will use Protector as part of the force it's building to guard its natural gas fields in the eastern Mediterranean. In the decades ahead, the offshore production platforms, due to start coming onstream in 2014, and other infrastructure will be a strategic target for Israel's adversaries.

Iran and its proxy, Hezbollah in Lebanon, are seen as particular threats, as is Syria and to a lesser extent Palestinian militants.

Hezbollah reportedly has hundreds of long-range missiles capable of hitting the offshore facilities south of Lebanon.