Why U.S. Patriot missiles failed to stop drones and cruise missiles attacking Saudi oil sites

The U.S. is having trouble defending against low-flying drones and cruise missiles after years of the Pentagon focusing on longer-range threats.

Sept. 23, 2019, 4:43 AM EDT
By Sébastien Roblin

The United States is sending American troops to the Middle East to provide better air and missile defenses after an aerial attack on Saudi oil targets last week. The raid began around 4 a.m. on the morning of Sept. 14, with explosions rippling across the Kurais and Abqaiq Aramco oil processing facilities inside Saudi Arabia as the sound of defensive automatic machine-gun fire rang in the air.

In theory, the oil facilities both lay under the defensive umbrella of Patriot PAC-2 surface-to-air missile batteries that the U.S. sold to Saudi Arabia to intercept aircraft and missiles up to 100 miles away. However, if Saudi radars detected the 18 triangular drones and seven cruise missiles (judging by recovered debris) that bombarded them last week, they did so too late. Instead, they were forced to fire sporadically with automatic weapons, which didn’t prevent widespread damage that temporarily disrupted shipments of 5.7 million barrels of oil daily — half of Saudi Arabia’s output.

Indeed, while the U.S. troops are intended to provide help against this type of threat — believed to have been launched by Iran — air attacks by low-flying drones and cruise missiles are exactly the types of systems the U.S. is having trouble defending against after years of focusing on longer-range threats.

Short-range air defense systems — or SHORADS in Army lingo — have existed almost as long as combat aircraft, and are used to protect vital bases and facilities, as well as troops on the front lines. In both the world wars, they consisted of heavy machine guns and rapid-fire cannons designed to rake warplanes as they swooped down to attack. During the Cold War, anti-aircraft artillery increasingly benefited from radar guidance, and were joined by heat-seeking missiles fired by vehicles or bazooka-like shoulder launchers.

However, after the fall of the Soviet Union, the U.S. Army sharply downsized its short-range anti-air capabilities in the belief that they were no longer greatly needed. They trusted that U.S. jet fighters could neutralize most enemy aircraft before they became a problem. Two threats that have grown significantly these days — drones and ground skimming cruise missiles — were minimal at that point: Armed drones were rare and expensive, and the Soviet Union was the only adversary that had many land-attack cruise missiles and it wasn’t expected that other countries, let alone terrorist groups, would develop them.

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