The United States is testing an Iron Dome missile-defence system in the Pacific amid growing Chinese aggression in the region.

The “dome” system, which Israel has deployed for years to block incoming Palestinian rockets and mortars, uses radar to identify and destroy incoming threats before they can cause damage.

News of the US shield system, first reported in the Wall Street Journal, follows recent revelations that Beijing secretly tested a missile with a hypersonic warhead, designed to fly at low orbit on an unpredictable path to evade interception.

China also boasts a growing fleet of bombers which can launch sea-skimming cruise missiles that could reach Guam, a US island territory in the Western Pacific.

The US tests signal that President Joe Biden is seeking to significantly bolster US abilities to counter Chinese military and economic expansion into the energy-rich waters and trade routes of the Indo-Pacific.

However, Beijing’s armed forces present a greater challenge than that of Palestinian militants.

China’s cruise missiles follow flat paths and fly far faster than the rockets used by Hamas, which makes intercepting them more difficult.

The US said the Iron Dome has successfully blocked missiles fired at below the speed of sound.

Such weaponry could be game-changing for Guam, which hosts about 190,000 American civilians and military personnel.

The remote island lies almost 3,000km from China, making it the closest US outpost to the rival superpower. It is known as the “tip of the spear” of US defence.

American military bases, including Andersen Air Force Base and the Naval Base Guam, occupy nearly 30pc of the island and are critical to the US Indo-Pacific policy.

The island also plays a significant role in Washington’s military strategies towards China, the Korean Peninsula, and potential flashpoints including the South China Sea and Taiwan.

Last September, China’s air force released a video showing nuclear-capable H-6 bombers carrying out a simulated attack on Guam’s air force base.

In 2017, the island was also the target of North Korean threats of missile strikes and “enveloping fire”.

The dome was developed by Israel’s Rafael Advanced Defence Systems Ltd in co-operation with Raytheon Technologies Corp and is only designed to destroy short-range rockets and artillery up to 65km away, meaning the US must also pursue separate plans to beef up its Pacific defences.