The Golden Dome, an ambitious, risky and expensive project

Since he ordered the Pentagon to deploy a space anti-missile shield by the end of his mandate, Donald Trump has estimated its cost at $175 billion. He promised that his Golden Dome would have a near 100% success rate, “ending forever the missile threat on American soil.”

However, the White House has revealed few details about this project which has been compared to the race for the atomic bomb during the Second World War and the Apollo moon landings. Analysts say it will take at least a decade to come to fruition and cost $1 trillion or more.

The Golden Dome would radically modify military doctrine and further militarize space without offering the complete protection promised by Mr. Trump, far from it.

For opponents of the program, its basic idea – flooding low Earth orbit with thousands of satellites to detect and destroy enemy missiles – is just a pipe dream that would destabilize the fragile international order that has prevented nuclear war since the 1950s.

“The Gold Dome may be the most dangerous idea Trump has ever had, and that’s saying something,” said Democratic Rep. Seth Moulton, a member of the Armed Services Committee.

Its supporters counter that the intensification of threats and technological progress mean that Star Wars must be revived., nickname for the Reagan-era strategic defense initiative canceled at the end of the Cold War. For years, they have been advocating for an anti-missile shield, as the United States does not have comprehensive protection of its territory.

China and Russia are strengthening their nuclear arsenals and funding the largest long-range weapons programs since the Cold War. They are adding hundreds of intercontinental ballistic missiles and new delivery systems to their arsenals, including hypersonic weapons designed to reach American cities at 6,400 km/h.

A limited defense

The United States has neglected its national missile defense, said Tom Karako, director of the missile defense project at the Center for Strategic and International Studies (CSIS), an independent research center. The $25 billion allocated this year by Mr. Trump to the Gold Dome is a “down payment to make up for years of neglect” in the face of long-awaited threats, he said.

Today, U.S. ballistic missile defense is designed to track an enemy missile from its launch and “propulsion phase” through its “intermediate phase” toward U.S. territory. Interceptor missiles located in Alaska and California are supposed to target enemy missiles.

The current system is designed to counter a small number of missiles from North Korea, not an attack from China or Russia.

If an incoming missile were detected, the United States would likely fire at least two missiles to intercept it. However, during several tests, the interceptor missiles missed the target.

China considers that the Golden Dome “would increase the risk of transforming space into a war zone and creating a space arms race, and that it would undermine the international security and arms control system”. Mao Ning, a spokesperson for China’s Foreign Ministry, urged the United States to abandon the idea and instead “take concrete measures to strengthen strategic trust among major countries and maintain global strategic stability.”

The Golden Dome is inspired by the Israeli Iron Dome. But this system only targets short-range missiles, in an area the size of New Jersey. The Golden Dome is expected to protect the entire United States against intercontinental missiles carrying multiple nuclear warheads.

The Congressional Budget Office estimates the cost of deploying space interceptors alone at $542 billion over 20 years. This amount would only make it possible to defend against one or two missiles launched by North Korea. Countering more threats requires considering one of the largest expenditures in Pentagon history, some experts warn.

According to Todd Harrison, a researcher at the American Enterprise Institute (AEI), a robust Gold Dome could cost up to $3.6 trillion over 20 years.

In May, Mr. Trump assigned Space Force Gen. Michael Guetlein to oversee the Golden Dome project. According to Mr. Harrison, when Mr. Trump promised a three-year, $175 billion rollout, he set an impossible goal for General Guetlein and created expectations that were “simply unrealistic.”

A low success rate

In addition to its short-range defense systems – Aegis, THAAD and Patriot – the Pentagon relies on the “ground-based intermediate defense system” to protect American territory. It consists of just 44 interceptor missiles, housed in silos buried in the tundra of Fort Greely, Alaska, and on the California coast at the Vandenburg Space Base.

In the event of an attack, the silos would open and a multi-stage rocket would emerge from each, leaving a trail of fire behind. As it flew toward its target, satellites and radars on the ground and at sea would transmit the speed, altitude and trajectory of the incoming missile.

Once in space, the American interceptor would release a spacecraft 1.4 m long, weighing 65 kg and equipped with thrusters and a sensor that protrudes like a horn. This “exoatmospheric interception vehicle” is designed to track its prey by speeding through space at 26,000 km/h, then destroy incoming missiles by ramming them. Experts compare it to “hitting a ball with a ball.”

However, in 20 tests since 1999, interceptor vehicles have missed the target almost one to two, with a success rate of just 55 percent, according to the American Physical Society (APS), a nonprofit science organization.

Worse still, considers the APS, these tests have not always reproduced real conditions, being “conducted under predefined conditions (…) favoring success (…) and the Pentagon has always judged these tests to be unrealistic on the operational level”.

According to Laura Grego of the Union of Concerned Scientists, the United States has spent more than $350 billion over 60 years on the program to defend against nuclear-tipped ballistic missiles. No result “has yet demonstrated its effectiveness against a real threat,” she writes.

Intercepting a missile in mid-flight is very difficult. Also, we try to target them shortly after their launch, during the “propulsion phase”, when their engines still running make them easier to spot. The Golden Dome interceptors would be placed in low orbit and swoop down on the target like a kamikaze during the brief boost phase.

But the staggering number of interceptors required makes many experts doubtful: “around 950 would be needed in orbit to ensure that at least one is always within range to intercept a missile during its propulsion phase,” according to AEI researcher Mr. Harrison. He calculated that to counter an attack of 10 missiles, it would be necessary to have placed at least 9,500 interceptors in space. At the American Physical Society, even more skeptical, they say that 16,000 are needed.

“You need so many more interceptors than missiles that it becomes unfeasible,” Mr. Harrison said.

Vulnerability in space

Even if it were effective, the Golden Dome would have an Achilles heel.

Such a concentration of satellites would be vulnerable to a nuclear explosion in space: a large part of them would fly apart in all directions and this orbital debris could put the entire network out of commission.

Without complete protection, deterrence remains the fundamental principle, said Doug Loverro, who has held various positions at NASA, the National Reconnaissance Office and the Pentagon, including deputy assistant secretary of Defense for space policy.

If the Golden Dome isn’t feasible, the Pentagon could make real progress expanding its ground systems well beyond its current 44 interceptors, he says. But even that would not guarantee total protection.

“Everyone knows that intercepting a massive attack is impossible,” he said. The question is: How many missiles do we need to defend against to turn back nuclear threats? »

This article was published in the Washington Post.

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